For more information regarding the security incident at F5, the actions we are taking to address it, and our ongoing efforts to protect our customers, click here.

Forum Discussion

Martin_Vlasko's avatar
Martin_Vlasko
Icon for Altocumulus rankAltocumulus
Dec 18, 2017

Load balance to node in the same DC where VIP is active

Hi,   We have following (simplified) scenario:   Two data centers: DC1, DC2.   Two F5 LTMs, one LTM in each DC, they run in active/standby mode and have one VIP configured.   Two applicat...
application delivery
irule
iRules
location awarness
LTM
Farshad_249798's avatar
Farshad_249798
Icon for Cirrus rankCirrus
Dec 18, 2017

You need to track a unique local id somehow and then use irule to select pool member based on that id. Haven’t tested this but I would use tcl_platform(machine) to get hostname assuming they are different.

 

Simon_Blakely's avatar
Simon_Blakely
Icon for Employee rankEmployee
Dec 21, 2017

The DC link latency is for the HA status messages exchanged between the two LTMs.

 

If latency increases too much, or HA packets get dropped, then you may get unexpected failover events.

 

You may wish to consider increasing the network failover timeout from 3 seconds

 

sol7249: Overview of the network failover timer

 

You should also ensure that you configure multiple unicast Failover Network addresses between the two LTMs, preferably using independent DC/DC links.