Re: test

[Jan-Henrik Haukeland]

Martin Pala <address@hidden> writes:

>   check process apache with pidfile /var/run/httpd.pid
>     start program = "/etc/init.d/apache start"      stop program =
>     "/etc/init.d/apache stop"
>     if failed port 80 protocol http then restart
>     alert address@hidden
>     depends on mysql
>
>   check host mysql on address 10.1.1.1
>     if failed port 3306 then stop
>     alert address@hidden
>
>   check process mmp with pidfile /var/run/mmp.pid
>     start program = "/etc/init.d/mmp start"      stop program =
>     "/etc/init.d/mmp stop"
>     if failed port 110 protocol pop then restart
>     alert address@hidden
>     depends on pop-backend1
>     depends on pop-backend2
>
>   check host pop-backend1 on address 10.1.1.1
>     if failed port 110 then stop
>     alert address@hidden
>
>   check host pop-backend2 on address 10.1.1.2
>     if failed port 110 then stop
>     alert address@hidden
>
>
> As you can see, host 10.1.1.1 provides pop3 as well as mysql, first
> syntax is more general and allows such setups.

Good point, with my proposal you can only have *one* check-host entry
in the control file per hostname/address. And the above example will
not work with this proposal. But on the other hand, I could argue that
you can roll-up the above entries into the process entry like so :-)

>   check process apache with pidfile /var/run/httpd.pid
>     start program = "/etc/init.d/apache start" 
>     stop program =  "/etc/init.d/apache stop"
>     if failed port 80 protocol http then restart
      if failed host 10.1.1.1 port 3306 then stop 
>     alert address@hidden
>     depends on mysql
>
>   check process mmp with pidfile /var/run/mmp.pid
>     start program = "/etc/init.d/mmp start"      stop program =
>     "/etc/init.d/mmp stop"
>     if failed port 110 protocol pop then restart
>     alert address@hidden
      if failed host 10.1.1.1 port 110 then stop
      if failed host 10.1.1.2 port 110 then stop

But, yes, you will miss out on the possibilities a depend tree can
provide. Hmm, I still like my proposal, but I can see that it's not so
flexible. How about a compromise? I think that it is a possibility
that host in your proposal could be mistaken for a real DNS host
record and not as a descriptive name, which in fact it is, so maybe we
should rewrite the statement to something like this?

   check connection pop-backend2 on host 10.1.1.2 # or host xzzy.org
     if failed port 110 then alert
     alert address@hidden


PS. I know we are in a freeze, and I know that I'm shooting myself in
the foot when I suggest that we add this remote host test in the
upcomming 4.0 release. But the reason is that it's very useful, and it
is easy to realize. It will take me (or anyone of you) only about 1-2
hours to add this check.

PPS. But the ICMP test you suggested in the other mail should be
postponed to a later release. It could be fun and I even have code
available for building a handmade ICMP ip-packet using a raw socket.

-- 
Jan-Henrik Haukeland