Can vrrp virtual IP be configured with same ip address as interface vlan 100.

[sajidkk2013]

Can we configure same ip address for interface vlan and virtual ip address in vrrp configuration. if yes, will it create any problem in the future. what is the best practice ?

TIA

[Georg Pauwen]

Hello,

not sure what you mean: the virtual router group, backup, and master addresses all need to be unique. So judging from that, the answer is no: you cannot use the same IP address.

[sajidkk2013]

I mean to say that:

if i have a vlan 100, which ip address is 192.168.5.2 255.255.255.0

can i give the same ip address to my vrrp group: plz check below:

int vlan 100

ip addresss 192.168.5.2 255.255.255.0     <<<<<<<<<

vrrp id 100

virtual ip address 192.168.5.2  <<<<<<<<<<

priority 255 

Actually, one of our client has this type of configuration in HP multilayer switch, working as a core.

We need make sure everything is good before starting the office.

TIA

[Georg Pauwen]

Hello,

that doesn't look right. If the group IP address is the same as either the master or the backup, if that IP address goes down, the entire group is not reachable, which defeats the entire purpose of VRRP. 

You need an IP address that is not configured anywhere for the VRRP group.

[Meheretab Mengistu · Accepted solution]

Hi,

Yes, you can configure the same IP address of a physical interface as Virtual IP address in VRRP configuration, which is not the case for HSRP. If a VRRP router owns the IP address of the virtual router and the IP address of the physical interface, this router will function as a virtual router master. 

The owner of the IP address is the master; and when the master fails, the backup router (or one of the backup routers) will take over the master role. When the original virtual master recovers, it will become master. Preemption is enabled by default. You can disable it using no vrrp preempt.

Look at the following to learn more:  https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipapp_fhrp/configuration/xe-3s/fhp-xe-3s-book/fhp-vrrp.html

I personally prefer to configure different IP address as the Virtual IP address (b/c I configure HSRP most of the time).

HTH,

Meheretab 

[sajidkk2013]

@Meheretab Mengistu 

Thanks you have reached to the point and I have tested too which is working fine.

This is what configuration was done in HP switches (master and backup) and were working fine in one of our client.

I also always configure HSRP each time and preferred as well, however, here scenario was different because devices were of HP.

So, I kept the same config as below:

vlan 5 

ip address 192.168.5.2 255.255.255.0    ----------------

name voice

untagged vlan 99

tagged vlan 5, 10, 40 

vrrp vrid 5

virtual-ip-address 192.168.5.2         -----------------

priority 255

preempt delay 10

enable 

exit

-----------------virtual ip and vlan ip was same--------------

Thanks,

[ganapareddysudha]

Hi Meheretab , 

Then what the VRRP IP address we need to configure in the backup router , is it the physical ip address of the master ?

Regards

Sudhakar Ganapareddy