[Xymon] ports check for a VIP...

[Christoph Zechner]

On 01/10/2021 16:21, Ian Diddams wrote:
> that's interesting
> 
> but presumably it would require something like
> 
> VIP V
> system A
> system B

My example is a bit different than your setup, since I'm only checking 
for connection and I'm doing this from two different xymon proxies which 
both report to the main xymon server. I suspect you have to define it 
like you wrote, yes.

> 
> V.ports = (V.conn && A.ports) ||  (V.conn && B.ports)

Do you also need the connection status as well? "ports" and "conn" are 
two different colums, I don't think mixing them would be wise?

> 
> but that would need A & B reporting on ports (ie 3306) - but one of 
> those will still always be red though?

That's why you need the "||", it's an or, so as long as one of your two 
hosts is green, your overall status is green.

> 
> 
> I suspect Ive not understood something!

I don't think so, I fear, my example was not really that great, sorry. 
As I said, I've never tried it with a ports check, only connection, 
which works like a charm.

Cheers
Christoph


> 
> 
> On Friday, 1 October 2021, 13:41:02 BST, Christoph Zechner 
> <zechner at vrvis.at> wrote:
> 
> 
> Hi,
> 
> On 01/10/2021 14:15, Ian Diddams via Xymon wrote:
>  > we have a HA mysql db cluster that runs with a VIP (drbd, pacemaker,
>  > corosync)
>  >
>  > we want a ports check for 3306 - but if we configure it for the two
>  > systems in the cluster one of them will always be red as its the slave
>  > and not running mysqld (it only runs on the master).
>  >
>  > the clear alternative is to somehow run a 3306 check on the VIP...  but
>  > the VIP itself is only an IP in hosts.cfg (so we can conn check its
>  > existence etc) and so isnt a client sending reports back to the server.
>  >
>  > any hints as to how we can acheive such a test ?
> 
> 
> You could try a combo status test, I've implemented these for connection
> tests, but it should work for port checks too, I guess (have not tried
> it though).
> 
> (all paths are for Debian, that's what I am using)
> 
> I defined a target in /etc/xymon/combo.cfg like this:
> 
> computer.conn = (computer1.conn || computer2.conn)
> 
> This returns green if one of the machines is green and also shows both
> statuses in the web interface.
> 
> I guess, this should also work with ports...
> 
> Good luck!
> Christoph
>