IRF and advantages

[raphT]

Hello folks,

I'm getting down in here because I'm looking for some information about the "power" of the IRF stacking.

I told my boss about it, and to be honest, the only thing I know about it, is that it allows to manage a couple of switches (in my actual case OfficeConnect 1950 swtiches) as a one chassis switch.

I setup such a token / ring installation with 4 switches for example purpose, and it all runs fine.  The thing is, I suppose there is much more possible to do with IRF than just central management of a couple of switches.

Actually, I found out a post on a HPE forum. https://community.arubanetworks.com/t5/Wired-Intelligent-Edge-Campus/IRF-in-depth-part-1-introduction/td-p/266841

The thing is, is it possible, to link up multiple IRF groups to 1 switch ?  The idea would be to, like represented on the last image of the first post in link above, to group the "middle" switches to 2 IRF groups (the first group would be with the top level switch, and the second for example, with the bottom level switches).  I have no idea if i'm clear in my explanation.

Or is it even possible to group all the switches together in one "big" stack ?

the thing is, the switches could be dispatched in different rack cabinets, dispatched on different floors in a building.  (For example, a 4 floor building could have a rack cabinet on each floor for cabling management and cost reduction).

The redundancy of the communication betweend al the switches is garanteed thanks to the IRF, or isn't it ?

What are other big advantages and plus points to setup and IRF system between switches.  What is the limit in IRF stacking (4 or 9 or even 10 switches ?)

Thank you all for every, even little information you could provide me asap.

RaphT.

[parnassus · Accepted solution]

Hi! IIRC the HPE OfficeConnect 1950 Switch series admits at most an IRF made of just four members...so you're pretty much limited on the number of IRF Member switches to be deployed in a single IRF Domain (=<4). Using proper SFP+ Transceivers ports or 10GBASE-T ports and point-to-point cablings you could place each IRF Member up to 90 meters far from the others (in a Chain [1 ]-- <90 meters -- [2] -- <90 meters -- [3] -- <90 meters -- [4] or in a Ring [1 ]-- <90 meters -- [2] -- <90 meters -- [3] -- <90 meters -- [4] -- <90 meters -- [1])...and stressing a little bit with SFP+ Long Range you can eventually overcome that limit...BUT you need to understand that the power of IRF is that it lets you to distribute traffic to connected Servers (or uplink/downlink Switches/other IRFs Domains) IF you connect them "multi-homed"...so a Server should be concurrently connected with 4 of its ports in LACP to each IRF Member (each link from the server on a particular IRF Members)...the same applies when you have Switch(es) or other IRFs...you can easily see that you will need a lot of cabling because a host/switch/IRF should be fully connected to all IRF Members and not only to a single particular IRF Member...so stretching an IRF on more buildings is totally possible but you need to understand WHY you need to do and HOW to benefit from having done so (where are your Servers? how you link them to the IRF? and so on...).

[raphT]

Dear Sir,

You just made me realise something important.  You use the IRF stack to connect "a same" device, for example a server, on the "4 switches" for example to ensure "high availability".

I just feel a it stupid I didn't realise it before.

Thank you for the click to make consider this.

Have a nice day.