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Forum Discussion

advanx_66706's avatar
advanx_66706
Icon for Nimbostratus rankNimbostratus
Oct 13, 2014

Member marked down even tough port is reachable

Hello,   I have 1 VS with 2 members, with https monitor. However, my LTM marked these members as down. From LTM I'am able to ping and telnet to member's port 443. If I changed the monitor to gatew...
Tim_K_92675's avatar
Tim_K_92675
Icon for Cirrostratus rankCirrostratus
Oct 14, 2014

This is an excellent article for troubleshooting health monitors:

 

https://support.f5.com/kb/en-us/solutions/public/12000/500/sol12531.html

 

I usually perform the following:

 

  1. Mimic the monitor request by using curl;
  2. Run a tcpdump on the monitor - something like: tcpdump -lnni 0.0 -Xs0 host x.x.x.x and port xxx
R_Marc's avatar
R_Marc
Icon for Nimbostratus rankNimbostratus
Nov 05, 2014
while curl can be useful, I personally find typing it in manually to be the best method. If it's HTTP telnet to the IP an port of the pool member. If it's ssl: openssl s_client -connect : In both cases you can type in the raw HTTP messages. I only rely on curl or tcpdump if its an MSSL connection and I don't have a client cert or if I need to post data. YMMV.