Event log - ERR20162

[Lilja_]

What is ERR20162?

ERR20162

2012-12-06 13:47:49 - SA02 - [1.1.1.1] userid(Realm)[Role] - Unable to open connection to server owa.domain.com:443

This the error that appears sometimes when accessing OWA2010 via web resource.

I cannot find any differences between a working session and a faulty one. The web requests looks the same.

If the user who receives the error message "Returns to previous page" and tries again, there is no problem.

[imanenvoy_]

Not much to go on but from the message and the fact that it works if the user trys again I'd suspect a timing issue, maybe a dns resolution timeout issue.

[jayLaiz_]

Hi , Are the OWA servers load balanced by any chance ? Regards, Jay

[Lilja_]

Yes, the OWA servers are load balanced with a F5 Big-IP...
Any experience with this, Jay?

[zanyterp_]

Does the big IP show any failure?
Is this replicable on-demand?
How does the load balancer work: each request goes to a different server or users are "assigned" to specific servers?
Can you capture a tcp dump of working & non-working?

To answer your question specifically, though, regarding the error: it means the connection to the server was denied/rejected/unreachable. Are all the CAS servers reachable directly?

[Lilja_]

No failures in BigIP (hard to see.. BigIP has really bad logging possibilities).

Not replicable on-demand, very intermittent.

BigIP sends the request to the server with "least connections". Will try to do a TCP dump on BigIP and SA boxes even though it is very far between failures..

[RexPGP_]

saw this when CAS was load balanced in 2007. If we made the load active passive went away. We are ready to move to 2010. I will follow this post.

[jayLaiz_]

Hi,

It does seem that the load balancer is not forwarding the traffic sometimes.A timing related setting on the LB could be causing this.A tcp dump from the Juniper when the issue is seen will be useful.

Regards,

Jai

[Lilja_]

@JayLaiz

Yes, it sure looks like that could be the problem, however - when accessing the load balanced URL from LAN, there are no problems.

[jayLaiz_]

Hi,

I think opening a JTAC case will be handy so that we can investigate the same.

If you point the web bookmark directly to individual OWA servers, we can see if the same issue exists

Regards,

Jay