topic Re: Cisco HSRP and Procurve VRRP in Switches, Hubs, and Modems

Cisco HSRP and Procurve VRRP

ywlow — Wed, 24 Nov 2010 03:33:39 GMT

Dear all, i got one cisco coreswitch to be converted to Procurve soon. But i'm not sure how the transitions from HSRP and VRRP will cause any problem. Attached the Cisco configuration. I can't set the virtual ip address differ with my vlan ip. For example VLAN 1 ip is 192.168.1.251, for the vrrp virtual ip i need to set back to point back the same vlan 1 ip. Is there any possibility that i can set to other virtual ip ?

Re: Cisco HSRP and Procurve VRRP

Natasha Samoylenko — Wed, 24 Nov 2010 07:16:52 GMT

VRRP requires virtual IP to be the same as VLAN IP only when switch configured as owner for that VLAN.
If you configure two switches as backup you can use any IP.

VRRP config:
vlan 10
ip address 10.1.10.2 255.255.255.0
tagged A3,A5

vrrp vrid 10
backup
virtual-ip-address 10.1.10.1 255.255.255.0
enable
exit
exit
vlan 20
ip address 10.1.20.2 255.255.255.0
tagged A1,A3

vrrp vrid 20
backup
virtual-ip-address 10.1.20.1 255.255.255.0
enable
exit
exit

Re: Cisco HSRP and Procurve VRRP

Mauro Furini — Wed, 24 Nov 2010 16:30:06 GMT

after that, remember to set the command "virtual-ip-ping"...

Re: Cisco HSRP and Procurve VRRP

ywlow — Thu, 25 Nov 2010 07:40:48 GMT

Natasha - Thanks for the info ! I've configure the the virtual ip same with my vlan ip.

Mauro Furini - As for the "virtual-ip-ping", i can't find it at the CLI command pdf. When the master down, the slave will take over. But it seems that we can't ping the gateway anymore.. does the virtual-ip-ping command enable us to ping the virtual ip ? Please guide me to this command. Thanks !

Re: Cisco HSRP and Procurve VRRP

Natasha Samoylenko — Thu, 25 Nov 2010 07:52:35 GMT

Yes, virtual-ip-ping command allow you to ping the virtual IP.
This command was in release notes, but I don't see it in configuration guide for software 14.xx.
In docs for 15.xx software it already listed.

From release notes:
=====
Enables or disables the response to a ping request for the switch. When enabled, all
VRs that are not Owners and are not explicitly disabled (see virtual-ip-ping enabled command) respond to ping requests sent to the VIP when the Backup VR is acting
as Master.
Default: Response to Virtual IP ping is disabled.
=====

sw(config)# router vrrp virtual-ip-ping

Re: Cisco HSRP and Procurve VRRP

Jeff Carrell — Thu, 25 Nov 2010 07:52:45 GMT

pinging the virtual ip addr when the backup is answering it, is available at K.14.47 code.

It is an enabled feature on each vrid, but you must enable it globally for it to work:

'router vrrp virtual-ip-ping'

hth...Jeff

Re: Cisco HSRP and Procurve VRRP

ywlow — Thu, 25 Nov 2010 09:42:41 GMT

Thanks Natasha & Jeff for the info ! Happy networking guys & gals !

Re: Cisco HSRP and Procurve VRRP

Mauro Furini — Mon, 29 Nov 2010 13:01:10 GMT

@Jeff: i don't understand a point: make sense enable the virtual-ip-ping in every vrrp instance when i must enable it globally to make it pingable?
maybe i'm in confusion :)

Re: Cisco HSRP and Procurve VRRP

Jeff Carrell — Mon, 29 Nov 2010 13:57:53 GMT

ywlow said "@Jeff: i don't understand a point: make sense enable the virtual-ip-ping in every vrrp instance when i must enable it globally to make it pingable?
maybe i'm in confusion :)"

The feature has 2 components for it to work:
1) a global command to enable it (which is off by default)
2) a command to enable it for each VRID (which is on by default).

So, to be able to ping a virtual-IP address (VIP) when the "backup router" is sponsoring the VIP, you need the feature to be on globally and locally.

After you enable the global command, you can then disable the pinging of a specific VIP if needed.

This feature is similar to configuring routing: a global command to enable it, and a local (in a vlan) command to configure the network for routing.

hth...Jeff

Re: Cisco HSRP and Procurve VRRP

Mauro Furini — Tue, 30 Nov 2010 08:43:25 GMT

aaaaaa :)
ok thanks, now is clear.
Another puzzle, while we're here: in your opinion, why is not possible to telnet the virtual ip but only the ip of the physic interface?

Re: Cisco HSRP and Procurve VRRP

Jeff Carrell — Tue, 30 Nov 2010 08:51:36 GMT

ywlow asked: "Another puzzle, while we're here: in your opinion, why is not possible to telnet the virtual ip but only the ip of the physic interface?"

Can't say, I've not tried to do that before, but probably why the special feature of pinging the VIP was added (which is not part of the VRRP spec and clearly stated as such in the docs).

Best practice, configure a loopback interface, that way there is always a known IP up and available on the switch, regardless of which interfaces are the active routed or not.

I generally configure the loopback interface and the router-id (OSPF) to be the same.

hth...Jeff