Planned long Power Cut to mains supply and powering down Network switches

[robintech]

Any advice or best practice for HP/Aruba Network switches or is there any way to shut them down gracefully as I can't find it, might be my bad luck but any switches that have died always seem to be after a power cut

The individual switches don't have UPS and the power cut is going to last longer than the Core switch UPS predicts it can handle, so need to shut down that as well.

 

So far have thought of

write memory in case something hasn't been saved then backup config to an offline drive and USB in case they corrupt

reboot them prior to shutdown? not sure why but seems a good idea

pull the power plugs out in case the power comes back intermittently

[DalekSec]

Only thing you can do, make sure config is saved and backup config to external device.

[3s-gtech]

We had this when we had major wiring works (think three phase 500A with fuses like drinks cans). It was off for a couple of weeks.

 

As part of the works, they fitted a changeover switch in the server room and a hookup for a generator. Kept us online throughout.

 

Practical to do this?

[robintech]

We had this when we had major wiring works (think three phase 500A with fuses like drinks cans). It was off for a couple of weeks.

 

As part of the works, they fitted a changeover switch in the server room and a hookup for a generator. Kept us online throughout.

 

Practical to do this?

 

Should have said this will only be about 90 minutes, or they say 45 minutes and I'd always double it to be safe, so don't think they would stretch to a proper backup generator

[Davit2005]

You should not experience any issues unless you power cycle the devices rapidly. If the switches are Aruba OS or HP ProCurve there is no option to shut them down gracefully. You could remove the power to prevent any issues caused by unstable power but that is all.

 

As @DalekSec mentions jus make sure the config is saved on the switch and you should employ some method to back them up automatically or manually back them up after changes by a putty CLI session or the GUI.

[Cazab]

Worth the hassle just unplugging any switches without a UPS preemptively?

[Jcx500]

Make sure your configuration is written and also back it up Edited October 24, 2023 by Jcx500

[Tys]

Worth the hassle just unplugging any switches without a UPS preemptively?

 

Good opportunity to fit some UPS's if they have to go down?

[Chris_Cook]

Same as above really.

 

I'd isolate them from the mains as they may want to do some testing on the wires (or wire the phases wrong). This will also help the electricians.

 

I'd shutdown the UPS so it doesn't discharge the battery. On APC you hold down the power button IIRC. Obviously shutdown any servers first.

 

Switches will generally cope well with just being turned off. If they needed a shutdown option there would be one.

 

Lastly (or firstly) make sure you have time scheduled in after power has been restored, but before your users come back so you can run round and test PCs and other items.

 

Probably worth having a backup plan incase a switch does die, but that should probably be in place anyway.

 

Our switches have been through plenty of power cuts and generally the only thing that goes wrong is the config not having been saved. This is one of the joys of Unifi - it automatically saves.

[3s-gtech]

I remember another thing from when we did ours - our ESXi box would always corrupt if it had the power pulled without shutdown. Had to reinstall the hypervisor every time (not the end of the world, but a pain and downtime!) Retired it in the end.

 

Hyper-V will sort of tolerate it (though never test that with a production server!) IME. If you’re running Exchange or SQL on a VM you may have a bad day.

 

Our Aruba switches don’t mind power cuts unless they’re stacked - often only one will boot properly but that may be a config quirk. Turning them both off and on will fix that.

[robintech]

Thanks all, have backed up all the configs and managed to automate it except for a few where they've nerfed SSH like the Aruba Instant On.

 

https://blog.feldmann.io/powershell/backup-hp-procurve-switches-via-ssh-tftp-and-powershell/

[enjay]

Worth the hassle just unplugging any switches without a UPS preemptively?

 

That's what we did in that position, that way we could plug them back in once the power was back and stable; also saved overloading the breakers when everything turned back on at once.

 

If you've got Unifi APs, you might want to check how your switches are uplinking after the restart. A couple of times, we've found the APs mesh to APs on another switch and take over as the uplink, rather than using the lovely 1Gb SFPs.

 

Make sure your switch backups are up-to-date, and you have a couple of spares in the cupboard ready to go. Aruba will honour the lifetime warranty, but I find that takes a few days.

[PotNoodleTech]

If it's work that could cause any sort of spike or sag - i would unplug the switches if you can (either pull power or if easier flick off the circuit breaker).

 

It's going on and off and on and off that can screw things up.

[MartinT]

Save the configuration files. Unplug the switches to prevent the 'on' spike from damaging them.