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Forum Discussion

suresh09_292033's avatar
suresh09_292033
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Jan 23, 2018
Solved

Fall back IP

What i understanding regarding fall back IP is that if all virtual servers in pool associated with wide ip are down then DNS will resolve to fall back ip but in my scenario it's happening differently...
application delivery
BIG-IP DNS
devops
  • Jason_Brown_314's avatar
    Jason_Brown_314
    Jan 31, 2018

    You need to have the alternate set to fallback for this to use that IP entry.

     

    Also, just to expand - I have just experienced this too and I understand that there is a level of caching done within DNS express in order to try to expedite the reply, you are also using a LDNS (presuming 10.10.10.10 isn't the DNS listener) to resolve this host you could get old answers. I disabled DNS express in my profile and it worked as I expected it should.

     

    being new to the GTM I am also still learning, so this is based on my troubleshooting only.

     

Jason_Brown_314's avatar
Jason_Brown_314
Icon for Nimbostratus rankNimbostratus
Jan 31, 2018

You need to have the alternate set to fallback for this to use that IP entry.

 

Also, just to expand - I have just experienced this too and I understand that there is a level of caching done within DNS express in order to try to expedite the reply, you are also using a LDNS (presuming 10.10.10.10 isn't the DNS listener) to resolve this host you could get old answers. I disabled DNS express in my profile and it worked as I expected it should.

 

being new to the GTM I am also still learning, so this is based on my troubleshooting only.

 

suresh09_292033's avatar
suresh09_292033
Icon for Nimbostratus rankNimbostratus
Jan 31, 2018

Thanks Brown, your suggestion worked for me.