Forum Discussion
NimbostratusLTM web service connections
Hello all,
I have a question that is leaving me clueless; I have no idea if this is caused by the F5 LTM v11 or by something else in our network.
We have two pairs of tomcat application servers, both running some webservices, lets call them A and B. I have a simple configuration in the F5, a VIP with two nodes talking over port 80 and everything seems happy.
However, when I try to reach the VIP of application B from the servers of application A it throws me a 404 message. When I try to reach the VIP of application B from other systems everything works fine. The 404 message seems to be generated by the F5, because the packets are not arriving on the application B servers (checked with Wireshark, and later even completely stopped the tomcat services).
I've checked the usual things locally and on the F5 (cleared the DNS cache, checked lookups, cleared ARP tables etc etc).
Is this something that could be caused by the LTM? Is there something I am missing? No compression or caching is used, it is a basic http round-robin profile.
Any help is appreciated.
regards,
Jaap
6 Replies
- Kevin_Stewart
Employee
At first guess, are all of the servers on the same subnet? If so, do you have SNAT enabled? 
Jaap_39600Hi Kevin,
Yes, the servers are in the same subnet and SNAT is enabled.... could this be the culprit?
Like the Johny Bravo avatar by the way :)
regards,
Jaap
Chris_Campbell1Cirrus
It would help if you could post some config or a network diagram, but I suspect you may need to investigate VIP bounceback. There is some info here http://support.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/ltm_configuration_guide_10_0_0/ltm_snat.html- Jaap_39600
What we are trying to do is in the attached drawing.
All servers run Windows with Tomcat 7, the HLB's are an active/passive pair hosting both the VIP's.
I've configured both the VIP's to use automap SNAT.
* edit * I can't seem to make my attachements visual - keep getting editor not supported errors. I'll look for a place to host them.
- Jaap_39600Problem solved... turned out to be a nasty typo on my side.
Thanks for the assistance! 
arthur_29895You may have had a typo but, I have noticed that unexpected packet splitting can really screw things up on soap calls
