23 files changed, 1515 insertions, 0 deletions

diff --git a/examples/redis-unstable/tests/sentinel/run.tcl b/examples/redis-unstable/tests/sentinel/run.tcl
new file mode 100644
index 0000000..4f2a656
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/run.tcl
@@ -0,0 +1,41 @@
+# Sentinel test suite.
+#
+# Copyright (C) 2014-Present, Redis Ltd.
+# All Rights reserved.
+#
+# Licensed under your choice of (a) the Redis Source Available License 2.0
+# (RSALv2); or (b) the Server Side Public License v1 (SSPLv1); or (c) the
+# GNU Affero General Public License v3 (AGPLv3).
+
+cd tests/sentinel
+source ../instances.tcl
+
+set ::instances_count 5 ; # How many instances we use at max.
+set ::tlsdir "../../tls"
+
+proc main {} {
+    parse_options
+    if {$::leaked_fds_file != ""} {
+        set ::env(LEAKED_FDS_FILE) $::leaked_fds_file
+    }
+    spawn_instance sentinel $::sentinel_base_port $::instances_count {
+        "sentinel deny-scripts-reconfig no"
+        "enable-protected-configs yes"
+        "enable-debug-command yes"
+    } "../tests/includes/sentinel.conf"
+
+    spawn_instance redis $::redis_base_port $::instances_count {
+        "enable-protected-configs yes"
+        "enable-debug-command yes"
+        "save ''"
+    }
+    run_tests
+    cleanup
+    end_tests
+}
+
+if {[catch main e]} {
+    puts $::errorInfo
+    cleanup
+    exit 1
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/00-base.tcl b/examples/redis-unstable/tests/sentinel/tests/00-base.tcl
new file mode 100644
index 0000000..7b64395
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/00-base.tcl
@@ -0,0 +1,210 @@
+# Check the basic monitoring and failover capabilities.
+source "../tests/includes/start-init-tests.tcl"
+source "../tests/includes/init-tests.tcl"
+
+foreach_sentinel_id id {
+    S $id sentinel debug default-down-after 1000
+}
+
+if {$::simulate_error} {
+    test "This test will fail" {
+        fail "Simulated error"
+    }
+}
+
+test "Sentinel command flag infrastructure works correctly" {
+    foreach_sentinel_id id {
+        set command_list [S $id command list]
+
+        foreach cmd {ping info subscribe client|setinfo} {
+            assert_not_equal [S $id command docs $cmd] {}
+            assert_not_equal [lsearch $command_list $cmd] -1
+        }
+
+        foreach cmd {save bgrewriteaof blpop replicaof} {
+            assert_equal [S $id command docs $cmd] {}
+            assert_equal [lsearch $command_list $cmd] -1
+            assert_error {ERR unknown command*} {S $id $cmd}
+        }
+
+        assert_error {ERR unknown subcommand*} {S $id client no-touch}
+    }
+}
+
+test "SENTINEL HELP output the sentinel subcommand help" {
+    assert_match "*SENTINEL <subcommand> *" [S 0 SENTINEL HELP]
+}
+
+test "SENTINEL MYID return the sentinel instance ID" {
+    assert_equal 40 [string length [S 0 SENTINEL MYID]]
+    assert_equal [S 0 SENTINEL MYID] [S 0 SENTINEL MYID]
+}
+
+test "SENTINEL INFO CACHE returns the cached info" {
+    set res [S 0 SENTINEL INFO-CACHE mymaster]
+    assert_morethan_equal [llength $res] 2
+    assert_equal "mymaster" [lindex $res 0]
+
+    set res [lindex $res 1]
+    assert_morethan_equal [llength $res] 2
+    assert_morethan [lindex $res 0] 0
+    assert_match "*# Server*" [lindex $res 1]
+}
+
+test "SENTINEL PENDING-SCRIPTS returns the information about pending scripts" {
+    # may or may not have a value, so assert greater than or equal to 0.
+    assert_morethan_equal [llength [S 0 SENTINEL PENDING-SCRIPTS]] 0
+}
+
+test "SENTINEL MASTERS returns a list of monitored masters" {
+    assert_match "*mymaster*" [S 0 SENTINEL MASTERS]
+    assert_morethan_equal [llength [S 0 SENTINEL MASTERS]] 1
+}
+
+test "SENTINEL SENTINELS returns a list of sentinel instances" {
+     assert_morethan_equal [llength [S 0 SENTINEL SENTINELS mymaster]] 1
+}
+
+test "SENTINEL SLAVES returns a list of the monitored replicas" {
+     assert_morethan_equal [llength [S 0 SENTINEL SLAVES mymaster]] 1
+}
+
+test "SENTINEL SIMULATE-FAILURE HELP list supported flags" {
+    set res [S 0 SENTINEL SIMULATE-FAILURE HELP]
+    assert_morethan_equal [llength $res] 2
+    assert_equal {crash-after-election crash-after-promotion} $res
+}
+
+test "Basic failover works if the master is down" {
+    set old_port [RPort $master_id]
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    assert {[lindex $addr 1] == $old_port}
+    kill_instance redis $master_id
+    foreach_sentinel_id id {
+        S $id sentinel debug ping-period 500
+        S $id sentinel debug ask-period 500  
+        wait_for_condition 1000 100 {
+            [lindex [S $id SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] 1] != $old_port
+        } else {
+            fail "At least one Sentinel did not receive failover info"
+        }
+    }
+    restart_instance redis $master_id
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    set master_id [get_instance_id_by_port redis [lindex $addr 1]]
+}
+
+test "New master [join $addr {:}] role matches" {
+    assert {[RI $master_id role] eq {master}}
+}
+
+test "All the other slaves now point to the new master" {
+    foreach_redis_id id {
+        if {$id != $master_id && $id != 0} {
+            wait_for_condition 1000 50 {
+                [RI $id master_port] == [lindex $addr 1]
+            } else {
+                fail "Redis ID $id not configured to replicate with new master"
+            }
+        }
+    }
+}
+
+test "The old master eventually gets reconfigured as a slave" {
+    wait_for_condition 1000 50 {
+        [RI 0 master_port] == [lindex $addr 1]
+    } else {
+        fail "Old master not reconfigured as slave of new master"
+    }
+}
+
+test "ODOWN is not possible without N (quorum) Sentinels reports" {
+    foreach_sentinel_id id {
+        S $id SENTINEL SET mymaster quorum [expr $sentinels+1]
+    }
+    set old_port [RPort $master_id]
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    assert {[lindex $addr 1] == $old_port}
+    kill_instance redis $master_id
+
+    # Make sure failover did not happened.
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    assert {[lindex $addr 1] == $old_port}
+    restart_instance redis $master_id
+}
+
+test "Failover is not possible without majority agreement" {
+    foreach_sentinel_id id {
+        S $id SENTINEL SET mymaster quorum $quorum
+    }
+
+    # Crash majority of sentinels
+    for {set id 0} {$id < $quorum} {incr id} {
+        kill_instance sentinel $id
+    }
+
+    # Kill the current master
+    kill_instance redis $master_id
+
+    # Make sure failover did not happened.
+    set addr [S $quorum SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    assert {[lindex $addr 1] == $old_port}
+    restart_instance redis $master_id
+
+    # Cleanup: restart Sentinels to monitor the master.
+    for {set id 0} {$id < $quorum} {incr id} {
+        restart_instance sentinel $id
+    }
+}
+
+test "Failover works if we configure for absolute agreement" {
+    foreach_sentinel_id id {
+        S $id SENTINEL SET mymaster quorum $sentinels
+    }
+
+    # Wait for Sentinels to monitor the master again
+    foreach_sentinel_id id {
+        wait_for_condition 1000 100 {
+            [dict get [S $id SENTINEL MASTER mymaster] info-refresh] < 100000
+        } else {
+            fail "At least one Sentinel is not monitoring the master"
+        }
+    }
+
+    kill_instance redis $master_id
+
+    foreach_sentinel_id id {
+        wait_for_condition 1000 100 {
+            [lindex [S $id SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] 1] != $old_port
+        } else {
+            fail "At least one Sentinel did not receive failover info"
+        }
+    }
+    restart_instance redis $master_id
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    set master_id [get_instance_id_by_port redis [lindex $addr 1]]
+
+    # Set the min ODOWN agreement back to strict majority.
+    foreach_sentinel_id id {
+        S $id SENTINEL SET mymaster quorum $quorum
+    }
+}
+
+test "New master [join $addr {:}] role matches" {
+    assert {[RI $master_id role] eq {master}}
+}
+
+test "SENTINEL RESET can resets the master" {
+    # After SENTINEL RESET, sometimes the sentinel can sense the master again,
+    # causing the test to fail. Here we give it a few more chances.
+    for {set j 0} {$j < 10} {incr j} {
+        assert_equal 1 [S 0 SENTINEL RESET mymaster]
+        set res1 [llength [S 0 SENTINEL SENTINELS mymaster]]
+        set res2 [llength [S 0 SENTINEL SLAVES mymaster]]
+        set res3 [llength [S 0 SENTINEL REPLICAS mymaster]]
+        if {$res1 eq 0 && $res2 eq 0 && $res3 eq 0} break
+    }
+    assert_equal 0 $res1
+    assert_equal 0 $res2
+    assert_equal 0 $res3
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/01-conf-update.tcl b/examples/redis-unstable/tests/sentinel/tests/01-conf-update.tcl
new file mode 100644
index 0000000..fe29bb0
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/01-conf-update.tcl
@@ -0,0 +1,50 @@
+# Test Sentinel configuration consistency after partitions heal.
+
+source "../tests/includes/init-tests.tcl"
+
+test "We can failover with Sentinel 1 crashed" {
+    set old_port [RPort $master_id]
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    assert {[lindex $addr 1] == $old_port}
+
+    # Crash Sentinel 1
+    kill_instance sentinel 1
+
+    kill_instance redis $master_id
+    foreach_sentinel_id id {
+        if {$id != 1} {
+            wait_for_condition 1000 50 {
+                [lindex [S $id SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] 1] != $old_port
+            } else {
+                fail "Sentinel $id did not receive failover info"
+            }
+        }
+    }
+    restart_instance redis $master_id
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    set master_id [get_instance_id_by_port redis [lindex $addr 1]]
+}
+
+test "After Sentinel 1 is restarted, its config gets updated" {
+    restart_instance sentinel 1
+    wait_for_condition 1000 50 {
+        [lindex [S 1 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] 1] != $old_port
+    } else {
+        fail "Restarted Sentinel did not receive failover info"
+    }
+}
+
+test "New master [join $addr {:}] role matches" {
+    assert {[RI $master_id role] eq {master}}
+}
+
+test "Update log level" {
+    set current_loglevel [S 0 SENTINEL CONFIG GET loglevel]
+    assert {[lindex $current_loglevel 1] == {notice}}
+
+    foreach {loglevel} {debug verbose notice warning nothing} {
+        S 0 SENTINEL CONFIG SET loglevel $loglevel
+        set updated_loglevel [S 0 SENTINEL CONFIG GET loglevel]
+        assert {[lindex $updated_loglevel 1] == $loglevel}
+    }
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/02-slaves-reconf.tcl b/examples/redis-unstable/tests/sentinel/tests/02-slaves-reconf.tcl
new file mode 100644
index 0000000..8196b60
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/02-slaves-reconf.tcl
@@ -0,0 +1,91 @@
+# Check that slaves are reconfigured at a latter time if they are partitioned.
+#
+# Here we should test:
+# 1) That slaves point to the new master after failover.
+# 2) That partitioned slaves point to new master when they are partitioned
+#    away during failover and return at a latter time.
+
+source "../tests/includes/init-tests.tcl"
+
+proc 02_test_slaves_replication {} {
+    uplevel 1 {
+        test "Check that slaves replicate from current master" {
+            set master_port [RPort $master_id]
+            foreach_redis_id id {
+                if {$id == $master_id} continue
+                if {[instance_is_killed redis $id]} continue
+                wait_for_condition 1000 50 {
+                    ([RI $id master_port] == $master_port) &&
+                    ([RI $id master_link_status] eq {up})
+                } else {
+                    fail "Redis slave $id is replicating from wrong master"
+                }
+            }
+        }
+    }
+}
+
+proc 02_crash_and_failover {} {
+    uplevel 1 {
+        test "Crash the master and force a failover" {
+            set old_port [RPort $master_id]
+            set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+            assert {[lindex $addr 1] == $old_port}
+            kill_instance redis $master_id
+            foreach_sentinel_id id {
+                wait_for_condition 1000 50 {
+                    [lindex [S $id SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] 1] != $old_port
+                } else {
+                    fail "At least one Sentinel did not receive failover info"
+                }
+            }
+            restart_instance redis $master_id
+            set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+            set master_id [get_instance_id_by_port redis [lindex $addr 1]]
+        }
+    }
+}
+
+02_test_slaves_replication
+02_crash_and_failover
+
+foreach_sentinel_id id {
+    S $id sentinel debug info-period 100
+    S $id sentinel debug default-down-after 1000
+    S $id sentinel debug publish-period 100
+}
+
+02_test_slaves_replication
+
+test "Kill a slave instance" {
+    foreach_redis_id id {
+        if {$id == $master_id} continue
+        set killed_slave_id $id
+        kill_instance redis $id
+        break
+    }
+}
+
+02_crash_and_failover
+02_test_slaves_replication
+
+test "Wait for failover to end" {
+    set inprogress 1
+    while {$inprogress} {
+        set inprogress 0
+        foreach_sentinel_id id {
+            if {[dict exists [S $id SENTINEL MASTER mymaster] failover-state]} {
+                incr inprogress
+            }
+        }
+        if {$inprogress} {after 100}
+    }
+}
+
+test "Restart killed slave and test replication of slaves again..." {
+    restart_instance redis $killed_slave_id
+}
+
+# Now we check if the slave rejoining the partition is reconfigured even
+# if the failover finished.
+02_test_slaves_replication
diff --git a/examples/redis-unstable/tests/sentinel/tests/03-runtime-reconf.tcl b/examples/redis-unstable/tests/sentinel/tests/03-runtime-reconf.tcl
new file mode 100644
index 0000000..bd6eecc
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/03-runtime-reconf.tcl
@@ -0,0 +1,225 @@
+# Test runtime reconfiguration command SENTINEL SET.
+source "../tests/includes/init-tests.tcl"
+set num_sentinels [llength $::sentinel_instances]
+
+set ::user "testuser"
+set ::password "secret"
+
+proc server_set_password {} {
+    foreach_redis_id id {
+        assert_equal {OK} [R $id CONFIG SET requirepass $::password]
+        assert_equal {OK} [R $id AUTH $::password]
+        assert_equal {OK} [R $id CONFIG SET masterauth $::password]
+    }
+}
+
+proc server_reset_password {} {
+    foreach_redis_id id {
+        assert_equal {OK} [R $id CONFIG SET requirepass ""]
+        assert_equal {OK} [R $id CONFIG SET masterauth ""]
+    }
+}
+
+proc server_set_acl {id} {
+    assert_equal {OK} [R $id ACL SETUSER $::user on >$::password allchannels +@all]
+    assert_equal {OK} [R $id ACL SETUSER default off]
+
+    R $id CLIENT KILL USER default SKIPME no
+    assert_equal {OK} [R $id AUTH $::user $::password]
+    assert_equal {OK} [R $id CONFIG SET masteruser $::user]
+    assert_equal {OK} [R $id CONFIG SET masterauth $::password]
+}
+
+proc server_reset_acl {id} {
+    assert_equal {OK} [R $id ACL SETUSER default on]
+    assert_equal {1} [R $id ACL DELUSER $::user]
+
+    assert_equal {OK} [R $id CONFIG SET masteruser ""]
+    assert_equal {OK} [R $id CONFIG SET masterauth ""]
+}
+
+proc verify_sentinel_connect_replicas {id} {
+    foreach replica [S $id SENTINEL REPLICAS mymaster] {
+        if {[string match "*disconnected*" [dict get $replica flags]]} {
+            return 0
+        }
+    }
+    return 1
+}
+
+proc wait_for_sentinels_connect_servers { {is_connect 1} } {
+    foreach_sentinel_id id {
+        wait_for_condition 1000 50 {
+            [string match "*disconnected*" [dict get [S $id SENTINEL MASTER mymaster] flags]] != $is_connect
+        } else {
+            fail "At least some sentinel can't connect to master"
+        }
+
+        wait_for_condition 1000 50 {
+            [verify_sentinel_connect_replicas $id] == $is_connect
+        } else {
+            fail "At least some sentinel can't connect to replica"
+        }
+    }
+}
+
+test "Sentinels (re)connection following SENTINEL SET mymaster auth-pass" {
+    # 3 types of sentinels to test:
+    # (re)started while master changed pwd. Manage to connect only after setting pwd
+    set sent2re 0
+    # (up)dated in advance with master new password
+    set sent2up 1
+    # (un)touched. Yet manage to maintain (old) connection
+    set sent2un 2
+
+    wait_for_sentinels_connect_servers
+    kill_instance sentinel $sent2re
+    server_set_password
+    assert_equal {OK} [S $sent2up SENTINEL SET mymaster auth-pass $::password]
+    restart_instance sentinel $sent2re
+
+    # Verify sentinel that restarted failed to connect master
+    wait_for_condition 100 50 {
+        [string match "*disconnected*" [dict get [S $sent2re SENTINEL MASTER mymaster] flags]] != 0
+    } else {
+        fail "Expected to be disconnected from master due to wrong password"
+    }
+
+    # Update restarted sentinel with master password
+    assert_equal {OK} [S $sent2re SENTINEL SET mymaster auth-pass $::password]
+
+    # All sentinels expected to connect successfully
+    wait_for_sentinels_connect_servers
+
+    # remove requirepass and verify sentinels manage to connect servers
+    server_reset_password
+    wait_for_sentinels_connect_servers
+    # Sanity check
+    verify_sentinel_auto_discovery
+}
+
+test "Sentinels (re)connection following master ACL change" {
+    # Three types of sentinels to test during ACL change:
+    # 1. (re)started Sentinel. Manage to connect only after setting new pwd
+    # 2. (up)dated Sentinel, get just before ACL change the new password
+    # 3. (un)touched Sentinel that kept old connection with master and didn't
+    #    set new ACL password won't persist ACL pwd change (unlike legacy auth-pass)
+    set sent2re 0
+    set sent2up 1
+    set sent2un 2
+
+    wait_for_sentinels_connect_servers
+    # kill sentinel 'sent2re' and restart it after ACL change
+    kill_instance sentinel $sent2re
+
+    # Update sentinel 'sent2up' with new user and pwd
+    assert_equal {OK} [S $sent2up SENTINEL SET mymaster auth-user $::user]
+    assert_equal {OK} [S $sent2up SENTINEL SET mymaster auth-pass $::password]
+
+    foreach_redis_id id {
+        server_set_acl $id
+    }
+
+    restart_instance sentinel $sent2re
+
+    # Verify sentinel that restarted failed to reconnect master
+    wait_for_condition 100 50 {
+        [string match "*disconnected*" [dict get [S $sent2re SENTINEL MASTER mymaster] flags]] != 0
+    } else {
+        fail "Expected: Restarted sentinel to be disconnected from master due to obsolete password"
+    }
+
+    # Verify sentinel with updated password managed to connect (wait for sentinelTimer to reconnect)
+    wait_for_condition 100 50 {
+        [string match "*disconnected*" [dict get [S $sent2up SENTINEL MASTER mymaster] flags]] == 0
+    } else {
+        fail "Expected: Sentinel to be connected to master"
+    }
+
+    # Verify sentinel untouched gets failed to connect master
+    wait_for_condition 100 50 {
+        [string match "*disconnected*" [dict get [S $sent2un SENTINEL MASTER mymaster] flags]] != 0
+    } else {
+        fail "Expected: Sentinel to be disconnected from master due to obsolete password"
+    }
+
+    # Now update all sentinels with new password
+    foreach_sentinel_id id {
+        assert_equal {OK} [S $id SENTINEL SET mymaster auth-user $::user]
+        assert_equal {OK} [S $id SENTINEL SET mymaster auth-pass $::password]
+    }
+
+    # All sentinels expected to connect successfully
+    wait_for_sentinels_connect_servers
+
+    # remove requirepass and verify sentinels manage to connect servers
+    foreach_redis_id id {
+        server_reset_acl $id
+    }
+
+    wait_for_sentinels_connect_servers
+    # Sanity check
+    verify_sentinel_auto_discovery
+}
+
+test "Set parameters in normal case" {
+
+    set info [S 0 SENTINEL master mymaster]
+    set origin_quorum [dict get $info quorum]
+    set origin_down_after_milliseconds [dict get $info down-after-milliseconds]
+    set update_quorum [expr $origin_quorum+1]
+    set update_down_after_milliseconds [expr $origin_down_after_milliseconds+1000]
+
+    assert_equal [S 0 SENTINEL SET mymaster quorum $update_quorum] "OK"
+    assert_equal [S 0 SENTINEL SET mymaster down-after-milliseconds $update_down_after_milliseconds] "OK"
+
+    set update_info [S 0 SENTINEL master mymaster]
+    assert {[dict get $update_info quorum] != $origin_quorum}
+    assert {[dict get $update_info down-after-milliseconds] != $origin_down_after_milliseconds}
+
+    #restore to origin config parameters
+    assert_equal [S 0 SENTINEL SET mymaster quorum $origin_quorum] "OK"
+    assert_equal [S 0 SENTINEL SET mymaster down-after-milliseconds $origin_down_after_milliseconds] "OK"
+}
+
+test "Set parameters in normal case with bad format" {
+
+    set info [S 0 SENTINEL master mymaster]
+    set origin_down_after_milliseconds [dict get $info down-after-milliseconds]
+
+    assert_error "ERR Invalid argument '-20' for SENTINEL SET 'down-after-milliseconds'*" {S 0 SENTINEL SET mymaster down-after-milliseconds -20}
+    assert_error "ERR Invalid argument 'abc' for SENTINEL SET 'down-after-milliseconds'*" {S 0 SENTINEL SET mymaster down-after-milliseconds "abc"}
+
+    set current_info [S 0 SENTINEL master mymaster]
+    assert {[dict get $current_info down-after-milliseconds] == $origin_down_after_milliseconds}
+}
+
+test "Sentinel Set with other error situations" {
+
+   # non-existing script
+   assert_error "ERR Notification script seems non existing*" {S 0 SENTINEL SET mymaster notification-script test.txt}
+
+   # wrong parameter number
+   assert_error "ERR wrong number of arguments for 'sentinel|set' command" {S 0 SENTINEL SET mymaster fakeoption}
+
+   # unknown parameter option
+   assert_error "ERR Unknown option or number of arguments for SENTINEL SET 'fakeoption'" {S 0 SENTINEL SET mymaster fakeoption fakevalue}
+
+   # save new config to disk failed
+   set info [S 0 SENTINEL master mymaster]
+   set origin_quorum [dict get $info quorum]
+   set update_quorum [expr $origin_quorum+1]
+   set sentinel_id 0
+   set configfilename [file join "sentinel_$sentinel_id" "sentinel.conf"]
+   set configfilename_bak [file join "sentinel_$sentinel_id" "sentinel.conf.bak"]
+
+   file rename $configfilename $configfilename_bak
+   file mkdir $configfilename
+
+   catch {[S 0 SENTINEL SET mymaster quorum $update_quorum]} err
+
+   file delete $configfilename
+   file rename $configfilename_bak $configfilename
+
+   assert_match "ERR Failed to save config file*" $err
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/04-slave-selection.tcl b/examples/redis-unstable/tests/sentinel/tests/04-slave-selection.tcl
new file mode 100644
index 0000000..3d2ca64
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/04-slave-selection.tcl
@@ -0,0 +1,5 @@
+# Test slave selection algorithm.
+#
+# This unit should test:
+# 1) That when there are no suitable slaves no failover is performed.
+# 2) That among the available slaves, the one with better offset is picked.
diff --git a/examples/redis-unstable/tests/sentinel/tests/05-manual.tcl b/examples/redis-unstable/tests/sentinel/tests/05-manual.tcl
new file mode 100644
index 0000000..95e8d41
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/05-manual.tcl
@@ -0,0 +1,94 @@
+# Test manual failover
+
+source "../tests/includes/init-tests.tcl"
+
+foreach_sentinel_id id {
+    S $id sentinel debug info-period 2000
+    S $id sentinel debug default-down-after 6000
+    S $id sentinel debug publish-period 1000
+}
+
+test "Manual failover works" {
+    set old_port [RPort $master_id]
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    assert {[lindex $addr 1] == $old_port}
+
+    # Since we reduced the info-period (default 10000) above immediately,
+    # sentinel - replica may not have enough time to exchange INFO and update
+    # the replica's info-period, so the test may get a NOGOODSLAVE.
+    wait_for_condition 300 50 {
+        [catch {S 0 SENTINEL FAILOVER mymaster}] == 0
+    } else {
+        catch {S 0 SENTINEL FAILOVER mymaster} reply
+        puts [S 0 SENTINEL REPLICAS mymaster]
+        fail "Sentinel manual failover did not work, got: $reply"
+    }
+
+    catch {S 0 SENTINEL FAILOVER mymaster} reply
+    assert_match {*INPROG*} $reply ;# Failover already in progress
+
+    foreach_sentinel_id id {
+        wait_for_condition 1000 50 {
+            [lindex [S $id SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] 1] != $old_port
+        } else {
+            fail "At least one Sentinel did not receive failover info"
+        }
+    }
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    set master_id [get_instance_id_by_port redis [lindex $addr 1]]
+}
+
+test "New master [join $addr {:}] role matches" {
+    assert {[RI $master_id role] eq {master}}
+}
+
+test "All the other slaves now point to the new master" {
+    foreach_redis_id id {
+        if {$id != $master_id && $id != 0} {
+            wait_for_condition 1000 50 {
+                [RI $id master_port] == [lindex $addr 1]
+            } else {
+                fail "Redis ID $id not configured to replicate with new master"
+            }
+        }
+    }
+}
+
+test "The old master eventually gets reconfigured as a slave" {
+    wait_for_condition 1000 50 {
+        [RI 0 master_port] == [lindex $addr 1]
+    } else {
+        fail "Old master not reconfigured as slave of new master"
+    }
+}
+
+foreach flag {crash-after-election crash-after-promotion} {
+    # Before each SIMULATE-FAILURE test, re-source init-tests to get a clean environment
+    source "../tests/includes/init-tests.tcl"
+
+    test "SENTINEL SIMULATE-FAILURE $flag works" {
+        assert_equal {OK} [S 0 SENTINEL SIMULATE-FAILURE $flag]
+
+        # Trigger a failover, failover will trigger leader election, replica promotion
+        # Sentinel may enter failover and exit before the command, catch it and allow it
+        wait_for_condition 300 50 {
+            [catch {S 0 SENTINEL FAILOVER mymaster}] == 0
+            ||
+            ([catch {S 0 SENTINEL FAILOVER mymaster} reply] == 1 &&
+            [string match {*couldn't open socket: connection refused*} $reply])
+        } else {
+            catch {S 0 SENTINEL FAILOVER mymaster} reply
+            fail "Sentinel manual failover did not work, got: $reply"
+        }
+
+        # Wait for sentinel to exit (due to simulate-failure flags)
+        wait_for_condition 1000 50 {
+            [catch {S 0 PING}] == 1
+        } else {
+            fail "Sentinel set $flag but did not exit"
+        }
+        assert_error {*couldn't open socket: connection refused*} {S 0 PING}
+
+        restart_instance sentinel 0
+    }
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/06-ckquorum.tcl b/examples/redis-unstable/tests/sentinel/tests/06-ckquorum.tcl
new file mode 100644
index 0000000..36c3dc6
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/06-ckquorum.tcl
@@ -0,0 +1,42 @@
+# Test for the SENTINEL CKQUORUM command
+
+source "../tests/includes/init-tests.tcl"
+set num_sentinels [llength $::sentinel_instances]
+
+test "CKQUORUM reports OK and the right amount of Sentinels" {
+    foreach_sentinel_id id {
+        assert_match "*OK $num_sentinels usable*" [S $id SENTINEL CKQUORUM mymaster]
+    }
+}
+
+test "CKQUORUM detects quorum cannot be reached" {
+    set orig_quorum [expr {$num_sentinels/2+1}]
+    S 0 SENTINEL SET mymaster quorum [expr {$num_sentinels+1}]
+    catch {[S 0 SENTINEL CKQUORUM mymaster]} err
+    assert_match "*NOQUORUM*" $err
+    S 0 SENTINEL SET mymaster quorum $orig_quorum
+}
+
+test "CKQUORUM detects failover authorization cannot be reached" {
+    set orig_quorum [expr {$num_sentinels/2+1}]
+    S 0 SENTINEL SET mymaster quorum 1
+    for {set i 0} {$i < $orig_quorum} {incr i} {
+        kill_instance sentinel [expr {$i + 1}]
+    }
+
+    # We need to make sure that other sentinels are in `DOWN` state
+    # from the point of view of S 0 before we executing `CKQUORUM`.
+    wait_for_condition 300 50 {
+        [catch {S 0 SENTINEL CKQUORUM mymaster}] == 1
+    } else {
+        fail "At least $orig_quorum sentinels did not enter the down state."
+    }
+
+    assert_error "*NOQUORUM*" {S 0 SENTINEL CKQUORUM mymaster}
+
+    S 0 SENTINEL SET mymaster quorum $orig_quorum
+    for {set i 0} {$i < $orig_quorum} {incr i} {
+        restart_instance sentinel [expr {$i + 1}]
+    }
+}
+
diff --git a/examples/redis-unstable/tests/sentinel/tests/07-down-conditions.tcl b/examples/redis-unstable/tests/sentinel/tests/07-down-conditions.tcl
new file mode 100644
index 0000000..dabbc14
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/07-down-conditions.tcl
@@ -0,0 +1,104 @@
+# Test conditions where an instance is considered to be down
+
+source "../tests/includes/init-tests.tcl"
+source "../../../tests/support/cli.tcl"
+
+foreach_sentinel_id id {
+    S $id sentinel debug info-period 1000
+    S $id sentinel debug ask-period 100
+    S $id sentinel debug default-down-after 3000
+    S $id sentinel debug publish-period 200
+    S $id sentinel debug ping-period 100
+}
+
+set ::alive_sentinel [expr {$::instances_count/2+2}]
+proc ensure_master_up {} {
+    S $::alive_sentinel sentinel debug info-period 1000
+    S $::alive_sentinel sentinel debug ping-period 100
+    S $::alive_sentinel sentinel debug ask-period 100
+    S $::alive_sentinel sentinel debug publish-period 100
+    wait_for_condition 1000 50 {
+        [dict get [S $::alive_sentinel sentinel master mymaster] flags] eq "master"
+    } else {
+        fail "Master flags are not just 'master'"
+    }
+}
+
+proc ensure_master_down {} {
+    S $::alive_sentinel sentinel debug info-period 1000
+    S $::alive_sentinel sentinel debug ping-period 100
+    S $::alive_sentinel sentinel debug ask-period 100
+    S $::alive_sentinel sentinel debug publish-period 100
+    wait_for_condition 1000 50 {
+        [string match *down* \
+            [dict get [S $::alive_sentinel sentinel master mymaster] flags]]
+    } else {
+        fail "Master is not flagged SDOWN"
+    }
+}
+
+test "Crash the majority of Sentinels to prevent failovers for this unit" {
+    for {set id 0} {$id < $quorum} {incr id} {
+        kill_instance sentinel $id
+    }
+}
+
+test "SDOWN is triggered by non-responding but not crashed instance" {
+    ensure_master_up
+    set master_addr [S $::alive_sentinel SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    set master_id [get_instance_id_by_port redis [lindex $master_addr 1]]
+
+    set pid [get_instance_attrib redis $master_id pid]
+    pause_process $pid
+    ensure_master_down
+    resume_process $pid
+    ensure_master_up
+}
+
+test "SDOWN is triggered by crashed instance" {
+    lassign [S $::alive_sentinel SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] host port
+    ensure_master_up
+    kill_instance redis 0
+    ensure_master_down
+    restart_instance redis 0
+    ensure_master_up
+}
+
+test "SDOWN is triggered by masters advertising as slaves" {
+    ensure_master_up
+    R 0 slaveof 127.0.0.1 34567
+    ensure_master_down
+    R 0 slaveof no one
+    ensure_master_up
+}
+
+if {!$::log_req_res} { # this test changes 'dir' config to '/' and logreqres.c cannot open protocol dump file under the root directory.
+test "SDOWN is triggered by misconfigured instance replying with errors" {
+    ensure_master_up
+    set orig_dir [lindex [R 0 config get dir] 1]
+    set orig_save [lindex [R 0 config get save] 1]
+    # Set dir to / and filename to "tmp" to make sure it will fail.
+    R 0 config set dir /
+    R 0 config set dbfilename tmp
+    R 0 config set save "1000000 1000000"
+    after 5000
+    R 0 bgsave
+    after 5000
+    ensure_master_down
+    R 0 config set save $orig_save
+    R 0 config set dir $orig_dir
+    R 0 config set dbfilename dump.rdb
+    R 0 bgsave
+    ensure_master_up
+}
+}
+
+# We use this test setup to also test command renaming, as a side
+# effect of the master going down if we send PONG instead of PING
+test "SDOWN is triggered if we rename PING to PONG" {
+    ensure_master_up
+    S $::alive_sentinel SENTINEL SET mymaster rename-command PING PONG
+    ensure_master_down
+    S $::alive_sentinel SENTINEL SET mymaster rename-command PING PING
+    ensure_master_up
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/08-hostname-conf.tcl b/examples/redis-unstable/tests/sentinel/tests/08-hostname-conf.tcl
new file mode 100644
index 0000000..263b06f
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/08-hostname-conf.tcl
@@ -0,0 +1,69 @@
+source "../tests/includes/utils.tcl"
+
+proc set_redis_announce_ip {addr} {
+    foreach_redis_id id {
+        R $id config set replica-announce-ip $addr
+    }
+}
+
+proc set_sentinel_config {keyword value} {
+    foreach_sentinel_id id {
+        S $id sentinel config set $keyword $value
+    }
+}
+
+proc set_all_instances_hostname {hostname} {
+    foreach_sentinel_id id {
+        set_instance_attrib sentinel $id host $hostname
+    }
+    foreach_redis_id id {
+        set_instance_attrib redis $id host $hostname
+    }
+}
+
+test "(pre-init) Configure instances and sentinel for hostname use" {
+    set ::host "localhost"
+    restart_killed_instances
+    set_all_instances_hostname $::host
+    set_redis_announce_ip $::host
+    set_sentinel_config resolve-hostnames yes
+    set_sentinel_config announce-hostnames yes
+}
+
+source "../tests/includes/init-tests.tcl"
+
+proc verify_hostname_announced {hostname} {
+    foreach_sentinel_id id {
+        # Master is reported with its hostname
+        if {![string equal [lindex [S $id SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] 0] $hostname]} {
+            return 0
+        }
+
+        # Replicas are reported with their hostnames
+        foreach replica [S $id SENTINEL REPLICAS mymaster] {
+            if {![string equal [dict get $replica ip] $hostname]} {
+                return 0
+            }
+        }
+    }
+    return 1
+}
+
+test "Sentinel announces hostnames" {
+    # Check initial state
+    verify_hostname_announced $::host
+
+    # Disable announce-hostnames and confirm IPs are used
+    set_sentinel_config announce-hostnames no
+    assert {[verify_hostname_announced "127.0.0.1"] || [verify_hostname_announced "::1"]}
+}
+
+# We need to revert any special configuration because all tests currently
+# share the same instances.
+test "(post-cleanup) Configure instances and sentinel for IPs" {
+    set ::host "127.0.0.1"
+    set_all_instances_hostname $::host
+    set_redis_announce_ip $::host
+    set_sentinel_config resolve-hostnames no
+    set_sentinel_config announce-hostnames no
+}
\ No newline at end of file
diff --git a/examples/redis-unstable/tests/sentinel/tests/09-acl-support.tcl b/examples/redis-unstable/tests/sentinel/tests/09-acl-support.tcl
new file mode 100644
index 0000000..a754dac
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/09-acl-support.tcl
@@ -0,0 +1,56 @@
+
+source "../tests/includes/init-tests.tcl"
+
+set ::user "testuser"
+set ::password "secret"
+
+proc setup_acl {} {
+    foreach_sentinel_id id {
+        assert_equal {OK} [S $id ACL SETUSER $::user >$::password +@all on]
+        assert_equal {OK} [S $id ACL SETUSER default off]
+
+        S $id CLIENT KILL USER default SKIPME no
+        assert_equal {OK} [S $id AUTH $::user $::password]
+    }
+}
+
+proc teardown_acl {} {
+    foreach_sentinel_id id {
+        assert_equal {OK} [S $id ACL SETUSER default on]
+        assert_equal {1} [S $id ACL DELUSER $::user]
+
+        S $id SENTINEL CONFIG SET sentinel-user ""
+        S $id SENTINEL CONFIG SET sentinel-pass ""
+    }
+}
+
+test "(post-init) Set up ACL configuration" {
+    setup_acl
+    assert_equal $::user [S 1 ACL WHOAMI]
+}
+
+test "SENTINEL CONFIG SET handles on-the-fly credentials reconfiguration" {
+    # Make sure we're starting with a broken state...
+    wait_for_condition 200 50 {
+        [catch {S 1 SENTINEL CKQUORUM mymaster}] == 1
+    } else {
+        fail "Expected: Sentinel to be disconnected from master due to wrong password"
+    }
+    assert_error "*NOQUORUM*" {S 1 SENTINEL CKQUORUM mymaster}
+
+    foreach_sentinel_id id {
+        assert_equal {OK} [S $id SENTINEL CONFIG SET sentinel-user $::user]
+        assert_equal {OK} [S $id SENTINEL CONFIG SET sentinel-pass $::password]
+    }
+
+    wait_for_condition 200 50 {
+        [catch {S 1 SENTINEL CKQUORUM mymaster}] == 0
+    } else {
+         fail "Expected: Sentinel to be connected to master after setting password"
+    }
+    assert_match {*OK*} [S 1 SENTINEL CKQUORUM mymaster]
+}
+
+test "(post-cleanup) Tear down ACL configuration" {
+    teardown_acl
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/10-replica-priority.tcl b/examples/redis-unstable/tests/sentinel/tests/10-replica-priority.tcl
new file mode 100644
index 0000000..d3f868a
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/10-replica-priority.tcl
@@ -0,0 +1,76 @@
+source "../tests/includes/init-tests.tcl"
+
+test "Check acceptable replica-priority values" {
+    foreach_redis_id id {
+        if {$id == $master_id} continue
+
+        # ensure replica-announced accepts yes and no
+        catch {R $id CONFIG SET replica-announced no} e
+        if {$e ne "OK"} {
+            fail "Unable to set replica-announced to no"
+        }
+        catch {R $id CONFIG SET replica-announced yes} e
+        if {$e ne "OK"} {
+            fail "Unable to set replica-announced to yes"
+        }
+
+        # ensure a random value throw error
+        catch {R $id CONFIG SET replica-announced 321} e
+        if {$e eq "OK"} {
+            fail "Able to set replica-announced with something else than yes or no (321) whereas it should not be possible"
+        }
+        catch {R $id CONFIG SET replica-announced a3b2c1} e
+        if {$e eq "OK"} {
+            fail "Able to set replica-announced with something else than yes or no (a3b2c1) whereas it should not be possible"
+        }
+
+        # test only the first redis replica, no need to double test
+        break
+    }
+}
+
+proc 10_test_number_of_replicas {n_replicas_expected} {
+    test "Check sentinel replies with $n_replicas_expected replicas" {
+        # ensure sentinels replies with the right number of replicas
+        foreach_sentinel_id id {
+            S $id sentinel debug info-period 100
+            S $id sentinel debug default-down-after 1000
+            S $id sentinel debug publish-period 100
+            set len [llength [S $id SENTINEL REPLICAS mymaster]]
+            wait_for_condition 200 100 {
+                [llength [S $id SENTINEL REPLICAS mymaster]] == $n_replicas_expected
+            } else {
+                fail "Sentinel replies with a wrong number of replicas with replica-announced=yes (expected $n_replicas_expected but got $len) on sentinel $id"
+            }
+        }
+    }
+}
+
+proc 10_set_replica_announced {master_id announced n_replicas} {
+    test "Set replica-announced=$announced on $n_replicas replicas" {
+        set i 0
+        foreach_redis_id id {
+            if {$id == $master_id} continue
+            #puts "set replica-announce=$announced on redis #$id"
+            R $id CONFIG SET replica-announced "$announced"
+            incr i
+            if { $n_replicas!="all" && $i >= $n_replicas } { break }
+        }
+    }
+}
+
+# ensure all replicas are announced
+10_set_replica_announced $master_id "yes" "all"
+# ensure all replicas are announced by sentinels
+10_test_number_of_replicas 4
+
+# ensure the first 2 replicas are not announced
+10_set_replica_announced $master_id "no" 2
+# ensure sentinels are not announcing the first 2 replicas that have been set unannounced
+10_test_number_of_replicas 2
+
+# ensure all replicas are announced
+10_set_replica_announced $master_id "yes" "all"
+# ensure all replicas are not announced by sentinels
+10_test_number_of_replicas 4
+
diff --git a/examples/redis-unstable/tests/sentinel/tests/11-port-0.tcl b/examples/redis-unstable/tests/sentinel/tests/11-port-0.tcl
new file mode 100644
index 0000000..a3e8bdb
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/11-port-0.tcl
@@ -0,0 +1,33 @@
+source "../tests/includes/init-tests.tcl"
+
+test "Start/Stop sentinel on same port with a different runID should not change the total number of sentinels" {
+        set sentinel_id [expr $::instances_count-1]
+        # Kill sentinel instance
+        kill_instance sentinel $sentinel_id
+
+        # Delete line with myid in sentinels config file
+        set orgfilename [file join "sentinel_$sentinel_id" "sentinel.conf"]
+        set tmpfilename "sentinel.conf_tmp"
+        set dirname "sentinel_$sentinel_id"
+
+        delete_lines_with_pattern $orgfilename $tmpfilename "myid"
+
+        # Get count of total sentinels
+        set a [S 0 SENTINEL  master mymaster]
+        set original_count [lindex $a 33]
+
+        # Restart sentinel with the modified config file
+        set pid [exec_instance "sentinel" $dirname $orgfilename]
+        lappend ::pids $pid
+
+        after 1000
+
+        # Get new count of total sentinel
+        set b [S 0 SENTINEL master mymaster]
+        set curr_count [lindex $b 33]
+
+        # If the count is not the same then fail the test
+        if {$original_count != $curr_count} {
+                fail "Sentinel count is incorrect, original count being $original_count and current count is $curr_count"
+        }
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/12-master-reboot.tcl b/examples/redis-unstable/tests/sentinel/tests/12-master-reboot.tcl
new file mode 100644
index 0000000..3d0d828
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/12-master-reboot.tcl
@@ -0,0 +1,112 @@
+# Check the basic monitoring and failover capabilities.
+source "../tests/includes/init-tests.tcl"
+
+
+if {$::simulate_error} {
+    test "This test will fail" {
+        fail "Simulated error"
+    }
+}
+
+
+# Reboot an instance previously in very short time but do not check if it is loading
+proc reboot_instance {type id} {
+    set dirname "${type}_${id}"
+    set cfgfile [file join $dirname $type.conf]
+    set port [get_instance_attrib $type $id port]
+
+    # Execute the instance with its old setup and append the new pid
+    # file for cleanup.
+    set pid [exec_instance $type $dirname $cfgfile]
+    set_instance_attrib $type $id pid $pid
+    lappend ::pids $pid
+
+    # Check that the instance is running
+    if {[server_is_up 127.0.0.1 $port 100] == 0} {
+        set logfile [file join $dirname log.txt]
+        puts [exec tail $logfile]
+        abort_sentinel_test "Problems starting $type #$id: ping timeout, maybe server start failed, check $logfile"
+    }
+
+    # Connect with it with a fresh link
+    set link [redis 127.0.0.1 $port 0 $::tls]
+    $link reconnect 1
+    set_instance_attrib $type $id link $link
+}
+
+
+test "Master reboot in very short time" {
+    set old_port [RPort $master_id]
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    assert {[lindex $addr 1] == $old_port}
+    
+    R $master_id debug populate 20000
+    R $master_id bgsave
+    R $master_id config set key-load-delay 1500
+    R $master_id config set loading-process-events-interval-bytes 1024
+    R $master_id config rewrite
+
+    foreach_sentinel_id id {
+        S $id SENTINEL SET mymaster master-reboot-down-after-period 5000
+        S $id sentinel debug ping-period 500
+        S $id sentinel debug ask-period 500 
+    }
+
+    kill_instance redis $master_id
+    reboot_instance redis $master_id
+    
+    set max_tries 1000
+    if {$::tsan} {
+        set max_tries 5000
+    }
+
+    foreach_sentinel_id id {        
+        wait_for_condition $max_tries 100 {
+            [lindex [S $id SENTINEL GET-MASTER-ADDR-BY-NAME mymaster] 1] != $old_port
+        } else {
+            fail "At least one Sentinel did not receive failover info"
+        }
+    }
+
+    # Reset configuration to avoid unnecessary delays
+    R $master_id config set key-load-delay 0
+    R $master_id config rewrite
+
+    set addr [S 0 SENTINEL GET-MASTER-ADDR-BY-NAME mymaster]
+    set master_id [get_instance_id_by_port redis [lindex $addr 1]]
+
+    # Make sure the instance load all the dataset
+    while 1 {
+        catch {[$link ping]} retval
+        if {[string match {*LOADING*} $retval]} {
+            after 100
+            continue
+        } else {
+            break
+        }
+    }
+}
+
+test "New master [join $addr {:}] role matches" {
+    assert {[RI $master_id role] eq {master}}
+}
+
+test "All the other slaves now point to the new master" {
+    foreach_redis_id id {
+        if {$id != $master_id && $id != 0} {
+            wait_for_condition 1000 50 {
+                [RI $id master_port] == [lindex $addr 1]
+            } else {
+                fail "Redis ID $id not configured to replicate with new master"
+            }
+        }
+    }
+}
+
+test "The old master eventually gets reconfigured as a slave" {
+    wait_for_condition 1000 50 {
+        [RI 0 master_port] == [lindex $addr 1]
+    } else {
+        fail "Old master not reconfigured as slave of new master"
+    }
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/13-info-command.tcl b/examples/redis-unstable/tests/sentinel/tests/13-info-command.tcl
new file mode 100644
index 0000000..ef9dc01
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/13-info-command.tcl
@@ -0,0 +1,47 @@
+source "../tests/includes/init-tests.tcl"
+
+test "info command with at most one argument" {
+    set subCommandList {}
+    foreach arg {"" "all" "default" "everything"} {
+        if {$arg == ""} {
+            set info [S 0 info]
+        } else {
+            set info [S 0 info $arg]
+        }
+        assert { [string match "*redis_version*" $info] }
+        assert { [string match "*maxclients*" $info] }
+        assert { [string match "*used_cpu_user*" $info] }
+        assert { [string match "*sentinel_tilt*" $info] }
+        assert { ![string match "*used_memory*" $info] }
+        assert { ![string match "*rdb_last_bgsave*" $info] }
+        assert { ![string match "*master_repl_offset*" $info] }
+        assert { ![string match "*cluster_enabled*" $info] }
+    }
+}
+
+test "info command with one sub-section" {
+    set info [S 0 info cpu]
+    assert { [string match "*used_cpu_user*" $info] }
+    assert { ![string match "*sentinel_tilt*" $info] }
+    assert { ![string match "*redis_version*" $info] }
+
+    set info [S 0 info sentinel]
+    assert { [string match "*sentinel_tilt*" $info] }
+    assert { ![string match "*used_cpu_user*" $info] }
+    assert { ![string match "*redis_version*" $info] }
+}
+
+test "info command with multiple sub-sections" {
+    set info [S 0 info server sentinel replication]
+    assert { [string match "*redis_version*" $info] }
+    assert { [string match "*sentinel_tilt*" $info] }
+    assert { ![string match "*used_memory*" $info] }
+    assert { ![string match "*used_cpu_user*" $info] }
+
+    set info [S 0 info cpu all]
+    assert { [string match "*used_cpu_user*" $info] }
+    assert { [string match "*sentinel_tilt*" $info] }
+    assert { [string match "*redis_version*" $info] }
+    assert { ![string match "*used_memory*" $info] }
+    assert { ![string match "*master_repl_offset*" $info] }
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/14-debug-command.tcl b/examples/redis-unstable/tests/sentinel/tests/14-debug-command.tcl
new file mode 100644
index 0000000..dccb992
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/14-debug-command.tcl
@@ -0,0 +1,9 @@
+source "../tests/includes/init-tests.tcl"
+
+test "Sentinel debug test with arguments and without argument" {
+   set current_info_period [lindex [S 0 SENTINEL DEBUG] 1]
+   S 0 SENTINEL DEBUG info-period 8888
+   assert_equal {8888} [lindex [S 0 SENTINEL DEBUG] 1] 
+   S 0 SENTINEL DEBUG info-period $current_info_period
+   assert_equal $current_info_period [lindex [S 0 SENTINEL DEBUG] 1]
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/15-config-set-config-get.tcl b/examples/redis-unstable/tests/sentinel/tests/15-config-set-config-get.tcl
new file mode 100644
index 0000000..f9831f8
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/15-config-set-config-get.tcl
@@ -0,0 +1,58 @@
+source "../tests/includes/init-tests.tcl"
+
+test "SENTINEL CONFIG SET and SENTINEL CONFIG GET handles multiple variables" {
+    foreach_sentinel_id id {
+        assert_equal {OK} [S $id SENTINEL CONFIG SET resolve-hostnames yes announce-port 1234]
+    }
+    assert_match {*yes*1234*} [S 1 SENTINEL CONFIG GET resolve-hostnames announce-port]
+    assert_match {announce-port 1234} [S 1 SENTINEL CONFIG GET announce-port]
+}
+
+test "SENTINEL CONFIG GET for duplicate and unknown variables" {
+    assert_equal {OK} [S 1 SENTINEL CONFIG SET resolve-hostnames yes announce-port 1234]
+    assert_match {resolve-hostnames yes} [S 1 SENTINEL CONFIG GET resolve-hostnames resolve-hostnames does-not-exist]
+}
+
+test "SENTINEL CONFIG GET for patterns" {
+    assert_equal {OK} [S 1 SENTINEL CONFIG SET loglevel notice announce-port 1234 announce-hostnames yes ]
+    assert_match {loglevel notice} [S 1 SENTINEL CONFIG GET log* *level loglevel]
+    assert_match {announce-hostnames yes announce-ip*announce-port 1234} [S 1 SENTINEL CONFIG GET announce*]
+}
+
+test "SENTINEL CONFIG SET duplicate variables" {
+    catch {[S 1 SENTINEL CONFIG SET resolve-hostnames yes announce-port 1234 announce-port 100]} e
+    if {![string match "*Duplicate argument*" $e]} {
+        fail "Should give wrong arity error"
+    }
+}
+
+test "SENTINEL CONFIG SET, one option does not exist" {
+    foreach_sentinel_id id {
+        assert_equal {OK} [S $id SENTINEL CONFIG SET announce-port 111]
+        catch {[S $id SENTINEL CONFIG SET does-not-exist yes announce-port 1234]} e
+        if {![string match "*Invalid argument*" $e]} {
+            fail "Should give Invalid argument error"
+        }
+    }
+    # The announce-port should not be set to 1234 as it was called with a wrong argument
+    assert_match {*111*} [S 1 SENTINEL CONFIG GET announce-port]
+}
+
+test "SENTINEL CONFIG SET, one option with wrong value" {
+    foreach_sentinel_id id {
+        assert_equal {OK} [S $id SENTINEL CONFIG SET resolve-hostnames no]
+        catch {[S $id SENTINEL CONFIG SET announce-port -1234 resolve-hostnames yes]} e
+        if {![string match "*Invalid value*" $e]} {
+            fail "Expected to return Invalid value error"
+        }
+    }
+    # The resolve-hostnames should not be set to yes as it was called after an argument with an invalid value
+    assert_match {*no*} [S 1 SENTINEL CONFIG GET resolve-hostnames]
+}
+
+test "SENTINEL CONFIG SET, wrong number of arguments" {
+    catch {[S 1 SENTINEL CONFIG SET resolve-hostnames yes announce-port 1234 announce-ip]} e
+    if {![string match "*Missing argument*" $e]} {
+        fail "Expected to return Missing argument error"
+    }
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/helpers/check_leaked_fds.tcl b/examples/redis-unstable/tests/sentinel/tests/helpers/check_leaked_fds.tcl
new file mode 100755
index 0000000..482b3e0
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/helpers/check_leaked_fds.tcl
@@ -0,0 +1,79 @@
+#!/usr/bin/env tclsh
+#
+# This script detects file descriptors that have leaked from a parent process.
+#
+# Our goal is to detect file descriptors that were opened by the parent and
+# not cleaned up prior to exec(), but not file descriptors that were inherited
+# from the grandparent which the parent knows nothing about. To do that, we
+# look up every potential leak and try to match it against open files by the
+# grandparent process.
+
+# Get PID of parent process
+proc get_parent_pid {_pid} {
+    set fd [open "/proc/$_pid/status" "r"]
+    set content [read $fd]
+    close $fd
+
+    if {[regexp {\nPPid:\s+(\d+)} $content _ ppid]} {
+        return $ppid
+    }
+
+    error "failed to get parent pid"
+}
+
+# Read symlink to get info about the specified fd of the specified process.
+# The result can be the file name or an arbitrary string that identifies it.
+# When not able to read, an empty string is returned.
+proc get_fdlink {_pid fd} {
+    if { [catch {set fdlink [file readlink "/proc/$_pid/fd/$fd"]} err] } {
+        return ""
+    }
+    return $fdlink
+}
+
+# Linux only
+set os [exec uname]
+if {$os != "Linux"} {
+    puts "Only Linux is supported."
+    exit 0
+}
+
+if {![info exists env(LEAKED_FDS_FILE)]} {
+    puts "Missing LEAKED_FDS_FILE environment variable."
+    exit 0
+}
+
+set outfile $::env(LEAKED_FDS_FILE)
+set parent_pid [get_parent_pid [pid]]
+set grandparent_pid [get_parent_pid $parent_pid]
+set leaked_fds {}
+
+# Look for fds that were directly inherited from our parent but not from
+# our grandparent (tcl)
+foreach fd [glob -tails -directory "/proc/self/fd" *] {
+    # Ignore stdin/stdout/stderr
+    if {$fd == 0 || $fd == 1 || $fd == 2} {
+        continue
+    }
+
+    set fdlink [get_fdlink "self" $fd]
+    if {$fdlink == ""} {
+        continue
+    }
+
+    # We ignore fds that existed in the grandparent, or fds that don't exist
+    # in our parent (Sentinel process).
+    if {[get_fdlink $grandparent_pid $fd] == $fdlink ||
+        [get_fdlink $parent_pid $fd] != $fdlink} {
+        continue
+    }
+
+    lappend leaked_fds [list $fd $fdlink]
+}
+
+# Produce report only if we found leaks
+if {[llength $leaked_fds] > 0} {
+    set fd [open $outfile "w"]
+    puts $fd [join $leaked_fds "\n"]
+    close $fd
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/includes/init-tests.tcl b/examples/redis-unstable/tests/sentinel/tests/includes/init-tests.tcl
new file mode 100644
index 0000000..ddb1319
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/includes/init-tests.tcl
@@ -0,0 +1,63 @@
+# Initialization tests -- most units will start including this.
+source "../tests/includes/utils.tcl"
+
+test "(init) Restart killed instances" {
+    restart_killed_instances
+}
+
+test "(init) Remove old master entry from sentinels" {
+    foreach_sentinel_id id {
+        catch {S $id SENTINEL REMOVE mymaster}
+    }
+}
+
+set redis_slaves [expr $::instances_count - 1]
+test "(init) Create a master-slaves cluster of [expr $redis_slaves+1] instances" {
+    create_redis_master_slave_cluster [expr {$redis_slaves+1}]
+}
+set master_id 0
+
+test "(init) Sentinels can start monitoring a master" {
+    set sentinels [llength $::sentinel_instances]
+    set quorum [expr {$sentinels/2+1}]
+    foreach_sentinel_id id {
+        S $id SENTINEL MONITOR mymaster \
+              [get_instance_attrib redis $master_id host] \
+              [get_instance_attrib redis $master_id port] $quorum
+    }
+    foreach_sentinel_id id {
+        assert {[S $id sentinel master mymaster] ne {}}
+        S $id SENTINEL SET mymaster down-after-milliseconds 2000
+        S $id SENTINEL SET mymaster failover-timeout 10000
+        S $id SENTINEL debug tilt-period 5000
+        S $id SENTINEL SET mymaster parallel-syncs 10
+        if {$::leaked_fds_file != "" && [exec uname] == "Linux"} {
+            S $id SENTINEL SET mymaster notification-script ../../tests/helpers/check_leaked_fds.tcl
+            S $id SENTINEL SET mymaster client-reconfig-script ../../tests/helpers/check_leaked_fds.tcl
+        }
+    }
+}
+
+test "(init) Sentinels can talk with the master" {
+    foreach_sentinel_id id {
+        wait_for_condition 1000 50 {
+            [catch {S $id SENTINEL GET-MASTER-ADDR-BY-NAME mymaster}] == 0
+        } else {
+            fail "Sentinel $id can't talk with the master."
+        }
+    }
+}
+
+test "(init) Sentinels are able to auto-discover other sentinels" {
+    verify_sentinel_auto_discovery
+}
+
+test "(init) Sentinels are able to auto-discover slaves" {
+    foreach_sentinel_id id {
+        wait_for_condition 1000 50 {
+            [dict get [S $id SENTINEL MASTER mymaster] num-slaves] == $redis_slaves
+        } else {
+            fail "At least some sentinel can't detect some slave"
+        }
+    }
+}
diff --git a/examples/redis-unstable/tests/sentinel/tests/includes/sentinel.conf b/examples/redis-unstable/tests/sentinel/tests/includes/sentinel.conf
new file mode 100644
index 0000000..1275236
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/includes/sentinel.conf
@@ -0,0 +1,9 @@
+# assume master is down after being unresponsive for 20s
+sentinel down-after-milliseconds setmaster 20000
+# reconfigure one slave at a time
+sentinel parallel-syncs setmaster 2
+# wait for 4m before assuming failover went wrong
+sentinel failover-timeout setmaster 240000
+# monitoring set
+sentinel monitor setmaster 10.0.0.1 30000 2
+
diff --git a/examples/redis-unstable/tests/sentinel/tests/includes/start-init-tests.tcl b/examples/redis-unstable/tests/sentinel/tests/includes/start-init-tests.tcl
new file mode 100644
index 0000000..b052350
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/includes/start-init-tests.tcl
@@ -0,0 +1,18 @@
+test "(start-init) Flush config and compare rewrite config file lines" {
+    foreach_sentinel_id id {
+        assert_match "OK" [S $id SENTINEL FLUSHCONFIG]
+        set file1 ../tests/includes/sentinel.conf
+        set file2 [file join "sentinel_${id}" "sentinel.conf"] 
+        set fh1 [open $file1 r]
+        set fh2 [open $file2 r]
+        while {[gets $fh1 line1]} {
+            if {[gets $fh2 line2]} {
+                assert [string equal $line1 $line2]
+            } else {
+                fail "sentinel config file rewrite sequence changed"
+            }
+        }
+        close $fh1
+        close $fh2  
+    }
+}
\ No newline at end of file
diff --git a/examples/redis-unstable/tests/sentinel/tests/includes/utils.tcl b/examples/redis-unstable/tests/sentinel/tests/includes/utils.tcl
new file mode 100644
index 0000000..adfd91c
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tests/includes/utils.tcl
@@ -0,0 +1,22 @@
+proc restart_killed_instances {} {
+    foreach type {redis sentinel} {
+        foreach_${type}_id id {
+            if {[get_instance_attrib $type $id pid] == -1} {
+                puts -nonewline "$type/$id "
+                flush stdout
+                restart_instance $type $id
+            }
+        }
+    }
+}
+
+proc verify_sentinel_auto_discovery {} {
+    set sentinels [llength $::sentinel_instances]
+    foreach_sentinel_id id {
+        wait_for_condition 1000 50 {
+            [dict get [S $id SENTINEL MASTER mymaster] num-other-sentinels] == ($sentinels-1)
+        } else {
+            fail "At least some sentinel can't detect some other sentinel"
+        }
+    }
+}
diff --git a/examples/redis-unstable/tests/sentinel/tmp/.gitignore b/examples/redis-unstable/tests/sentinel/tmp/.gitignore
new file mode 100644
index 0000000..f581f73
--- /dev/null
+++ b/examples/redis-unstable/tests/sentinel/tmp/.gitignore
@@ -0,0 +1,2 @@
+redis_*
+sentinel_*