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Forum Discussion

Jim_Araujo's avatar
Jim_Araujo
Icon for Nimbostratus rankNimbostratus
Nov 04, 2020

Same IP Shared between multiple GTM LIsteners

Hi All, I hope this is a simple anwser because I don't believe this is setup correctly. We have two i2800 F5s running DNS and LTM feature sets. LTM portion works as expected with device-group and tra...
application delivery
BIG-IP DNS
devops
Giorgi_Gujabidz's avatar
Giorgi_Gujabidz
Icon for Cirrus rankCirrus
Nov 10, 2020

As Pete already mentioned, it is definitely HA configuration issue, If you have not configured MAC Masquerade feature, in L2 requests coming from BIG IP devices, source MAC is always active member's MAC address. So when failover occurs, some switches couldn't clear there ARP caches quickly enough and hence there continue to give away the same MAC in ARP responses. So you have to configure masquerading, this will create virtual MAC for your listener IP which will float with it after failover.

 

Here is how to configure this feature: https://support.f5.com/csp/article/K13502

And this is very helpful article by f5 about how to choose unique MAC: https://support.f5.com/csp/article/K3523

 

Hope that helps.

// GIorgi