topic To stack or not in ExtremeSwitching (EXOS/Switch Engine)

To stack or not

nixcraft — Wed, 17 Feb 2021 20:34:32 GMT

Hi everybody. I’m designing an environment with two X440-G2 edge switches and two X620-16t rack switches for servers.

At first I thought that I’d create two separate stacks and connect the two with dual 10Gb links and LACP. But looks like I can also create a single stack that includes all four switches. They will be close enough that I could use the stock DAC cables. Then I wouldn’t even need the extra 10Gb licenses for the X440s.

What are the pros and cons of either option, if there are really anything noteworthy?

Re: To stack or not

Stefan_K_ — Wed, 17 Feb 2021 21:25:26 GMT

Pros:

simplier manageability
less licenses required for XMC (this will most possibly change in the future, but it seems that this isn’t really required here anyways)

Cons:

the performance/features/limits are limited by the “weakest” switch in the stack. In your case this shouldn’t be an issue because X440G2 and X620 are quite similar. (See EXOS release notes → Limits)
When you upgrade the firmware the whole stack goes down. You can’t update the Edge-Switches without interrupting the connectivity between server (or between servers and storage when using iSCSI for example)

Personally I wouldn’t stack server- and core-switches, but in your case (small environment) it seems suitable.

Re: To stack or not

nixcraft — Wed, 17 Feb 2021 21:54:51 GMT

Thanks for that. I like the idea of separation as well for server and end-user switches. Less impact for the whole network during upgrades seems like good choice as well.

So perhaps I’ll go for two stacks, the 10Gb licenses for X440-G2 aren’t that much more price wise.