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konradp_385235's avatar
konradp_385235
Icon for Nimbostratus rankNimbostratus
Mar 05, 2019

GMT / LTM (DC 1+ DC 2) active/standby virtual server health check fails

We have 4x virtual F5 running in 2 data centers (DC1 + DC2). The GTM config is that they are all part of the same sync-group each configured with a listener IP (self-none float).

 

For the LTM configuration, it is setup in active-standby (one pair per DC).

 

The issue that I am seeing is that when I configure a virtual server on a stand-by LTM in the DNS section, the health check fails. Even though the same virtual server is in green status on the primary LTM.

 

I am not sure if this has something to do with the fact that the LTM is in standby but from my perspective, I would like to have all 4 GTMs serving DNS requests and monitor virtual servers configured on the LTM setup in act/standby.

 

Does anyone else run in that configuration? Any advice would be appreciated it.

 

Thanks.

 

application delivery
BIG-IP DNS
LTM

1 Reply

  • Rico's avatar
    Rico
    Icon for Cirrus rankCirrus
    Mar 05, 2019

    Make sure you have your LTMs setup as an HA pair. If you dont add in both devices when configuring the Server in BIG-IP DNS, it will send a health monitor check to the standby device and the standby device will not respond as expected.