Do not enable the watchdog by default

Any administrative operation, performed using maxadmin or maxctrl,
that takes longer than the watchdog timeout will cause MaxScale to
be killed and restarted by the watchdog.

Documentation/Getting-Started/Configuration-Guide.md

@@ -1978,3 +1978,9 @@ enabled MaxScale will check that all threads are running and notify systemd
 with a "keep-alive ping".
 
 Systemd reference: https://www.freedesktop.org/software/systemd/man/systemd.service.html
+
+*NOTE*: In 2.3.1 there is a deficiency that manifests itself so that if
+_any_ administrative operation, performed using _maxctrl_ or _maxadmin_,
+takes longer that the specified watchdog timeout, then the watchdog will
+kill and restart MaxScale. Please take that into account before enabling
+the watchdog.

Documentation/Release-Notes/MaxScale-2.3.1-Release-Notes.md

@@ -89,9 +89,13 @@ enabled and MaxScale will behave accordingly. Please see the
 [documentation](Getting-Started/Configuration-Guide.md#systemd-watchdog)
 for more details.
 
-By default the watchdog timeout is 60 seconds. That is, if MaxScale is
-hung, then systemd will detect that and restart MaxScale after slightly
-more than 60 seconds.
+By default the watchdog is disabled.
+
+*NOTE*: In 2.3.1 there is a deficiency that manifests itself so that if
+_any_ administrative operation, performed using _maxctrl_ or _maxadmin_,
+takes longer that the specified watchdog timeout, then the watchdog will
+kill and restart MaxScale. Please take that into account before enabling
+the watchdog.
 
 ### Miscellaneous
 

etc/maxscale.service.in

@@ -20,7 +20,9 @@ ExecStart=@CMAKE_INSTALL_PREFIX@/@MAXSCALE_BINDIR@/maxscale
 TimeoutStartSec=120
 LimitNOFILE=65535
 StartLimitBurst=0
-WatchdogSec=60s
+#Please see the MaxScale release notes and/or watchdog documentation
+#before turning the watchdog on.
+#WatchdogSec=60s
 
 # Only relevant when MaxScale is linked with -fsanitize=address
 Environment=ASAN_OPTIONS=abort_on_error=1