Forum Discussion

Burg35_12657's avatar
Burg35_12657
Icon for Nimbostratus rankNimbostratus
Mar 09, 2011

Member Server communcation to VIP

I am new to F5s so I appoligize , The issue I am having is that I need a member server in one pool to communicate with the VIP of another pool. The VIP and members are in different VLANS. I am able to telnet to port 80 on the vip but I am assuming this is the F5 answering because I see no traffic on either of the member servers in the VIP. Sant is on and there are Self IPs for each subnet. Any suggestions would be helpful.

 

 

Thanks
config
design
  • Chris_Miller's avatar
    Chris_Miller
    Icon for Altostratus rankAltostratus
    Mar 09, 2011
    Are all the pool members in the same VLAN? If so, you'll need to use SNAT otherwise the pool members will reply to each other without going through LTM so you'll be "out-of-state."
  • Chris_Miller's avatar
    Chris_Miller
    Icon for Altostratus rankAltostratus
    Mar 09, 2011
    What are you using for SNAT? AutoMap or a SNAT Pool? After telnetting, can you do a GET and see if you get a reply? If you're using an HTTP Profile on the VIP, LTM won't make a connection to the pool member until you've done that so simply telnetting isn't a perfect representation.
  • L4L7_53191's avatar
    L4L7_53191
    Icon for Nimbostratus rankNimbostratus
    Mar 14, 2011
    Chris makes a good point: be sure and use a valid request with your telnet sessions. You're dead right that the connection is established to the VIP (3 way handshake). What happens next is that the BigIP is waiting for a set of complete HTTP headers to parse, then it'll forward the request on. So in case you've not done so, be sure and type something like:

     

     

    telnet foo.com 80

     

    GET /index.html HTTP/1.1

     

    Host:

     

    Connection: close

     

     

    ...followed by two enter key hits to complete the HTTP request properly.

     

     

    Then see what you find on the server side. You should see the request come into the logs. If not, you'll need to start tcpdump-ing to figure out where the traffic is going.

     

    -Matt