HSRP configuration in different domain

[shahulhameed]

Hello Everybody

I have two datacenter called DC1 & DC2 each DC has two core switch CO1 primary and CO2 secondary.

Both DCs are different VTP domains. HSRP configured for DATA and VOICE VLANS for redundancy if any CORE down another one will take care of it. For users DATA and VOICE I didn't face any problem in both DC access locations because they are same VLAN but different IP segment. I have two CCM servers for VOICE, now both are in DC1 the servers are in VLAN 185 I configured HSRP in DC1 core locations as follows

CORE-1

description ITD-ITD112G-DATA11

ip address 10.1.185.2 255.255.255.0

no ip redirects

no ip unreachables

no ip proxy-arp

ip igmp version 3

standby 11 ip 10.1.185.1

standby 11 timers msec 250 msec 750

standby 11 priority 150

standby 11 preempt delay minimum 180

standby 11 authentication DES3auth

end

CORE-2

description ITD-ITD112G-DATA11

ip address 10.1.185.3 255.255.255.0

no ip redirects

no ip unreachables

no ip proxy-arp

ip igmp version 3

standby 11 ip 10.1.185.1

standby 11 timers msec 250 msec 750

standby 11 preempt delay minimum 180

standby 11 authentication DES3auth

end

I want to move one CCM to DC2 so before move the CCM server I tried to configure HSRP for the CCM VLAN 185 in DC2 as follows

CORE-1

description ITD-ITD112G-DATA11

ip address 10.1.185.4 255.255.255.0

no ip redirects

no ip unreachables

no ip proxy-arp

ip igmp version 3

standby 11 ip 10.1.185.1

standby 11 timers msec 250 msec 750

standby 11 priority 110

standby 11 preempt delay minimum 180

standby 11 authentication DES3auth

end

CORE-2

description ITD-ITD112G-DATA11

ip address 10.1.185.5 255.255.255.0

no ip redirects

no ip unreachables

no ip proxy-arp

ip igmp version 3

standby 11 ip 10.1.185.1

standby 11 timers msec 250 msec 750

standby 11 preempt delay minimum 180

standby 11 authentication DES3auth

end

After I configured HSRP the users in DC2 location IP phones are disconnected from CCM (both are in DC1) If I shut the interface VLAN 185 the users IP phones are working fine.

Please advice me how to configure HSRP in different VTP domains.

[Giuseppe Larosa · Accepted solution]

Hello Shahul,

the problem is not related to the fact that there are two different VTP domains involved.

if DC1 to DC2 connectivity is layer3 based when you add vlan185 in DC2 with same ip subnet you are creating a duplicated subnet.

You should use the clustering over the WAN option that allows to have servers in different ip subnets if one waydelay is less then 20 ms.

So you can use a different ip subnet in DC2 and you need to add the moved server as a new subscriber.

if you have fast links like GE links and the two sites are not far (few hundreds km apart is supported) this clustering over WAN can work well.

You need also to use QoS to protect inter-cluster traffic.

Hope to help

Giuseppe