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SP_266134
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Oct 14, 2016

F5 Pool monitors http traffic and node Offline (Enabled) - Pool member has been marked down by a monitor

Guys, I have configured to nodes to have a http monitor. I can access the default port 80 http application form the server and also from my client. The moment I add these nodes to the pool. I don’t see it getting Green. The port 80 traffic is open, so I can browse on the server. Offline (Enabled) - Pool member has been marked down by a monitor From the server: I don’t see any firewall issues on the server. IIS is running on the server. How can I get the http monitoring working from F5. Any pointer is appreciated.

 

5 Replies

  • ICMP is working but not http monitor. from my desktop http: requests are resolving that means the server port 80 s not blocked and it is functioning correct. ?

     

  • Can you login to the F5 cmd and do a curl on http url? It should respond back with 200 OK.

    curl -v http://abc.com

    -Jinshu

  • Please list the configuration in question. You mention configuring nodes to use an HTTP monitor, which could be a problem. The nodes are only an IP address, so you probably need to stick with ICMP monitor only on the node level.

     

    Please see the configuration guide section "Monitor-to-node association" for more details on this.

     

  • I always find the best path to verify that the F5 can indeed get to a pool member is by doing a curl from the terminal of the F5 itself. This will ensure proper routing, and will ensure that the F5 does indeed have access to the port specified. It might be taking an unexpected path, which will cause the traffic to be received from a random self ip.

     

    >tracepath -nn {ipaddress} The first entry will in most cases be the selfip in which monitor traffic will be originating from >curl -vv {ipaddress}

    From the verbose output, you should get a pretty good understanding of what is happening. Additionally because you are using the base http health monitor, rather than an HTTP/1.1 compatible one, you can see how the server will respond to the request with telnet from the F5

     

    >telnet {ipaddress} 80 GET /

    Again inspecting the output received from the server, it might shed some light on your issue.