HSRP over mutiple 6509 switches

read this please

and this

Hi Roman,

thanks for the quick response....

Are these notes pointing at Native IOS on the cat, and not the hybrid CatOS/IOS? I am running the later...

Thanks

Pete.

my bad both links are for "native"

To answer one question HSRP uses hello packets to the multicast add of

224.0.0 2 ( all outers)

A better way would be to use the command: set system highavailability enable on the Sup cards and

redundancy high-availability single-router-mode on the RSM's or MFC's

That way CatA-supB and CatB-supB only become active when the A sup fails it makes the configs easier to look at because at any given time you only have two Sup's active versus all four. However your config's would work as is.

Cool.

I have the system highavail... enabled on the switch (not the MSFC) and I believe that this sync's the port config (eg vlan info) between the 2 sups in the that chassis.?

So in single router mode, I only configure one sup on each Cat (using the above config) and it is sync'd to the other sup?

Is the only benefit of doing it this way to reduce the admin overhead of maintaining 4 configs instead of 2, or this there a more technical reason?

Many thanks for your replies...

Pete.

If you are running in hybrid mode, you should give consideration to migrating to native as a first step.

It will help simplify the configuration considerablely

"So in single router mode, I only configure one sup on each Cat (using the above config) and it is sync'd to the other sup? "

Yes, when you make a config change on the active sup it is automaticly pushed down to the standby SUP/MSFC thats one of the things I really like; before, someone would add and interface to the active and not the standby let alone setup HSRP. Bottom line is it won't be two long before all 4 of your config's are out of whack.

"Is the only benefit of doing it this way to reduce the admin overhead of maintaining 4 configs instead of 2, or this there a more technical reason?"

Thats one reason, but in testing you'll find that HSRP hello's are sent every 3 sec with a default hold-time of 10 sec and a transition time of

5 to 10 sec, so if a sup card fails youll have about a 25 second outage, with single router mode the transition from standby sup to active sup is almost undetectable.

Hi Merv,

Not possible i'm afraid. We're running hybrid around our organisation, and this is the 1st installation with 2 cats.

Thanks.

Well your organization is missing out on some very useful features ...

Thank you all for your input.

I'll look into native mode a bit more, but I think the costs of upgrading all our switches will be too much currently. I'll also look more into the single router mode options for faster failover.

With thanks,

Pete.

also take a look at Catalyst modular software for future consideration.

This is key to non-stop forwarding which is where IOS is headed in higher end boxes

and

NSF with stateful switch-over

BTW how many switches do you have in your network

Hi Merv.

Sorry for the dealy in replying - I though I had posted...

I have 2 cats on my local site, 2 on another, and 1 on a third. Unfortunately, they all fall under different financial control, with some being tighter that others!

Many thanks to everyone,

Pete.