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mbrandon32's avatar
mbrandon32
Icon for Cirrus rankCirrus
May 20, 2024

GSLB - Monitoring LTM VIP load balancing via iRule

In one of our environments we are configuring a single LTM VIP and load balancing multiple applications via an iRule. We currently have other LTM environments integrated via iQuery with our GTM for G...
application delivery
gslb
gslb servers
GSLBPOOL
gtm
GTM DNS
zamroni777's avatar
zamroni777
Icon for MVP rankMVP
May 20, 2024

GTM serves DNSlayer that its dns response only contains ip addresses without any L4 port numbers.
in case the GTM pool member is LTM VS, then GTM response contains their VIP address (without the L4 port number).

as work around, you can make dummy LTM VS (using same VIP but different ports or different source address) containing monitors to each 100 applications, hence it will be marked Down if any of the monitor fails.
then bind this new LTM VS to the GTM pool, replacing the real (non dummy) LTM VS.