CSS : Quick Question

[sampusarkar]

Hello :

   I have two CSSs configured with the following config;

CSS1

==========

circuit VLAN122

  ip address 10.110.252.11 255.255.255.240

    ip virtual-router 102 priority 99 preempt

    ip redundant-vip 102 10.110.252.12

CSS2

==========

************************** CIRCUIT **************************

circuit VLAN122

  ip address 10.110.252.10 255.255.255.240

    ip virtual-router 102 priority 90

    ip redundant-vip 102 10.110.252.12

If I want to CSS to be master. What command should I use ? Can I increase the priority of backup CSS 100 or 99 and will it help backup CSS

to be Master?

Regards

Arjun

[jason.espino]

Hello Arjun,

I assume CSS1 is currently assumed the master role between the 2 CSS's.  If that's the case changing the priority on CSS2 to 99 may or may not allow it to assume the master role.  The reason why is the preempt command on CSS1 may not allow the backup CSS2 to assume the master role.  If the preempt is removed and both CSS's have the same priority and for whatever reason BOTH have assumed the master role the CSS whose (real) interface has the smaller IP address will relinquish mastership to the other CSS.  If the preempt was removed from CSS1 and CSS2 had a higher priority of 100 then there is a strong possibility that CSS2 will assume the master role.  This would be done through the VRRP messages exchanged between the 2 load balancers.

One thing I wanted to ask, why are interested in changing the mastership role between the CSS's if you have designated one (CSS1) to have a higher priority and preempt?

- Jason