Do switches sometimes need rebooting?

Question

In your opinion, do switches sometimes need a restart?

I'm asking this because today our NAS stopped working properly, and was only fixed when we restarted the switch it was attached to.

Solution 1

Good ones - no.

Bad ones - sometimes, but that's only because they're badly engineered.

That's really all there is to it, really - if a switch requires regular rebooting then it's either faulty, or just a very poor switch. That said, as with all things with IT - sometimes things do go wrong. If it's the first time it's happened, keep an eye on it but don't worry too much.

I've seen it more often with consumer routers (Especially ones doing NAT) that are being used in the wrong environment. In those cases, it's more likely to be the NAT table filling up or perhaps a CPU related issues which are really down to just misusing the equipment.

It's plausible that you have a consumer switch which is just being pushed too hard.

Solution 2

Restarting will achieve a lot of things, most of which can be achieved without restarting. One of the things that restarting will often do is clear the logs in memory, so you won't know anything about the problem after you restarted.

So if you are seeing this behaviour frequently, rather than just blindly restarting, take a look at what is going on with the switch (assuming that is possible with the switch - it may not be if the switch is consumer grade, or the problem is really serious).

Knowing what the problem actually is will help you fix the problem, rather than just working around it.

Comments

[Dan]

Actually, this is a fair point - I blindly assumed it would be an unmanaged switch.

[symcbean]

If you're regularly re-organising your lan (or have multi-pathing), and unless you've disabled auto-learning on the switch, then even good ones need to have the routing table reset. Power cycling is usually a simple way of doing this.

[Dan]

@symcbean Well, a L2 switch shouldn't need resetting and neither should a decent L3 switch.

[woliveirajr]

+1 after reading the question, I would say "good ones no, bad ones sometimes..." and just found that answered. perfect.

[Tom O'Connor]

Even good ones sometimes crash. At $dayjob we had an Extreme go bad and start locking up hard. Warranty replacement though, so it was replaced..

[Dan]

@TomO'Connor I'd put that in the faulty category. The point is, a decent switch shouldn't require any kind of regular reboot

[the-wabbit]

... except for updating the firmware

[Austin ''Danger'' Powers]

How do higher-quality switches avoid problems with the NAT table filling up? I've always wondered this