IRF - daisy chain VS ring

[Mauro Furini]

Hi all,

     I have recently configured a couple of A7510 in IRF, but I cant't be able to configure them on a ring topology, but only in daisy chain.

In the same day I have configured a couple of 5500 in a ring topology, at this point why the 7510 doesn't like the ring?

In your experience, with only 2 switch to connect in IRF, wich deployment did you use/prefere?

thanks

[paulgear]

Hi Mauro,

I've only done IRF on 5500s & 5820s, but in both cases, I used a ring (although the difference when you're talking about 2 switches is fairly minimal).  One thing I found when using the 5500s was that you had to cross over the cables - i.e. port 1 on switch 1 goes to port 2 on switch 2, not port 1 on switch 2.  That may or may not be related the issue you're experiencing.  Do you get any messages in the logs?  What do the IRF display commands show?

[Apachez-]

The point of using a ring instead of daisy chain is of course for both performance AND redundancy. In a daisy chain if one interface breaks your IRF will have a split brain (compared to a ring where the IRF is still intact).

[manuel.bitzi]

Dear Mauro

Only two IRF Members are supported with 7510. Because that ring topo makes no sense and only daisy chain is supported.

7503 and 7506 support four IRF Members => ring and daisy chain are supported.

br

Manuel

[RyanBiddle]

I found in an environment of 6 5500's in a ring,

when it came to an upgrade, Even though I had A/B switches in each rack,

The Rolling upgrade left the other switches dead untill they regained the new stack with the new code.

Forceing me to take downtime in an environment where that wasn't acceptable.

(Instead of taking downtime I meticulesly broke the ring into 3 stacks of 2. it does the 2 switch stack upgrade flawlessly)

Because of this experience, I'd still caution to maintain 2 managment domains, and build all other HA domains with that in mind.

I heard IRF2 promises improvements here. But, with IRF1 not playing with IRF2 what does it matter.

[Apachez-]

Or just upgrade the units one by one by hand?

Sure it will take slightly longer time but this way you can test with one and see so everything works. If some IRF code was changed then you wont take number 2 from the same rack but rather number 3 and then number 5. This way the network is still operational.