[xymon] bbtest yellow-mystery

[Bill Arlofski]

On 07/12/10 08:29, Buchan Milne wrote:
> On Monday, 12 July 2010 09:13:26 Carl Melgaard wrote:
>> Hi,
>>
>> One of our AD-servers went down for maintenance for 1 week, and I disabled
>>  the conn+dns tests in Xymon for that period. Now the "bbtest" column
>>  suddenly goes yellow, and indicates that DNS lookups takes 450+ seconds
>>  now (indicating that the DNS-check for the maintenanced server is still
>>  active).
> 
> No, it indicates that the Xymon server is taking a long time to resolve host 
> names to IP addresses. You may need to configure the DNS client settings on the 
> Xymon server (e.g. adjust the 'server' parameters in /etc/resolv.conf).
> 
> If you have most IP addresses hardcoded correctly in bb-hosts, you may want to 
> add the 'testip' flag to the relevant lines of bb-hosts.
> 
> Regards,
> Buchan


Hi Carl... You can check the "bbtest" page on yout Xymon server and take a
look at the "DNS Statistics" section to gain a little more insight to what
appears to be a dns resolution/timeout issue.

If you are indeed experiencing dns resolution issues as Buchan suggests, you
might consider doing what I do on my Xymon servers - I generally install
djbdns, a small, fast, caching name server on my Xymon servers which reduces
the load on the network's main dns server, and also significantly speeds up
the dns tests.

Not to argue with Buchan, but I'd generally recommend against using testip if
possible only because it will just cause more work down the road if/when a
server, or system has an IP address changed. (it happens)

Having said, that, I'd  also say that using "testip" as a troubleshooting tool
can be helpful, but I would remove it once you have isolated and have solved
the real cause of your dns symptoms.

Hope this helps.

-- 
Bill Arlofski
Reverse Polarity, LLC