SIP traffic - Minor problem with OPTIONS messages - advice needed :)

Hello all,

 

I just need advice for my "problem" if someone knows or had the similar problem.

 

Rough architecture is like this:

 

Opencloud Rhino (2 nodes) < = > F5 Big-IP (software version 10.2.4) < = > MSS (6 nodes)

 

 

So on LB i have SIP-monitor which i use to check availability of Rhino nodes -> this is working fine

 

MSS also have health monitor to check availability of LB. So all 6 MSS's nodes are sending OPTIONS messages to LB, and LB should answer on them... If not then MSS receives alarm and the MSS node, on whose requests LB didn't answer, will mark LB like "dead" for time being.

 

So in my case when there is no SIP traffic between network elements, then OPTIONS messages are just fine (all requests are answered). In case when there is a SIP traffic then sometimes for some (random) calls that OPTIONS message exchange is affected somehow and LB is not answering to all MSS requests (there is no answer to max 2 of 6 nodes). Note this is happening only for a short period of time (1-2 min and then again it is fine) and maybe few times per day, so it is not a big deal, but customer wants to know why this is happening...

 

I really don't know the answer on that question, so if someone has some knowledge/experience/suggestion i would be very grateful.

 

 

Regards,

 

Zvone