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samson_wick_203
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Sep 22, 2015

How to change LTM behavior when a virtual server is offline but enabled

When a node is marked offline the F5 answers differently when administratively offline than when offline due to a monitor.

In the example below "VS 1" is offline because of a monitor, and "VS 2" is offline because I manually marked it offline. These virtual servers are otherwise configured identically and sitting in front of identical pools of identically configured servers.

VS 1 is "Offline (Enabled)":

telnet 10.252.40.84 1025
Trying 10.252.40.84...
Connected to 10.252.40.84.
Escape character is '^]'.
Connection closed by foreign host.

VS 2 is "Offline (Disabled)":

telnet 10.252.40.86 1025
Trying 10.252.40.86...
telnet: Unable to connect to remote host: Connection refused

Is there a way to get them both to behave like "VS 2" does in the example when marked offline because of a monitor?

2 Replies

  • In VS1, the virtual is sending a TCP CLOSE and in VS2 the virtual is sending a TCP RST. Either situation results in a terminated connection from the client perspective. Why do you need to change the default behavior?

     

  • I'm dealing with a proprietary application with an application layer load balancing scheme which is looking for a TCP RST to determine a node is down and not to send work to it.