this post was submitted on 06 Nov 2025
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Proxmox

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Proxmox VE is a complete, open-source server management platform for enterprise virtualization. It tightly integrates the KVM hypervisor and Linux Containers (LXC), software-defined storage and networking functionality, on a single platform. With the integrated web-based user interface you can manage VMs and containers, high availability for clusters, or the integrated disaster recovery tools with ease.

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I'm running Proxmox 9 on a server with currently a single LXC running. On no apparent time schedule, within a day but frequently within an hour, the host will stop responding to SSH, pings and the web UI stops updating. However, the LXC continues to run happily. The only way to bring the host back up is to power cycle the server.

Has anyone got any troubleshooting tips?

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[–] SpikesOtherDog@ani.social 3 points 2 weeks ago (2 children)

It could be a failing drive. If you have a spare drive you could reinstall on there and import your guests. Could save hours of troubleshooting software ghosts.

[–] ProfessorHoover@infosec.pub 2 points 2 weeks ago (1 children)

Thanks, I'll try that. Something odd is also happening where I just realised I can access it by tailscale, but not the local network so that narrows it down a bit, but I'll give the spare drive a go first.

[–] spitfire@lemmy.world 1 points 2 weeks ago (1 children)

Hmm, are you running Tailscale on the Proxmox VE, not in a container/VM?

[–] ProfessorHoover@infosec.pub 1 points 1 week ago (1 children)

I'm running it on both the host and the container

[–] spitfire@lemmy.world 1 points 1 week ago

There you go :) I’ve had a Pi running Tailscale and it ws not reachable using its local IP (it was accessible when using Tailscale IP) when Tailscale was started. When I was using Tailscale for site-to-site connectivity (subnet router) I ran it in an LXC container on PVE, so I’d advise you try that. Avoiding installation of additional software on the hypervisor seems like a smart idea - whenever I can I put stuff in containers/VMs.

[–] spitfire@lemmy.world 1 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

If it’s a failing drive running dmesg will tell you that.

[–] SpikesOtherDog@ani.social 2 points 2 weeks ago

Good point.

[–] AbidanYre@lemmy.world 2 points 2 weeks ago (3 children)

Very niche case, but I saw pretty much the same thing.

I was running from an SD card on the iDSDM in a Dell server. The module was flaky and I'd have to power it all off and pop the SD card out and back in then bring it back up.

Unlikely to be the same thing, but maybe some breadcrumbs to start your search

[–] possiblylinux127@lemmy.zip 1 points 1 week ago

Side note: do not install Proxmox on cheap storage mediums

[–] SpikesOtherDog@ani.social 1 points 2 weeks ago (1 children)

Hardware issues are often the case. I'll put my advice as a top comment.

[–] AbidanYre@lemmy.world 1 points 2 weeks ago

Good point. All my VMs were on a zfs array.

It seemed like enough of the system was in ram that it could still run, but anything that needed the root file system was out of luck.

[–] ProfessorHoover@infosec.pub 1 points 2 weeks ago (1 children)

I wonder if it is the same issue. I installed on an emmc module which isn't recommended by Proxmox but I thought I'd get away with it. I might try reinstalling to another drive and see if it still happens.

[–] AbidanYre@lemmy.world 1 points 2 weeks ago

Huh. Maybe it is related then. For what it's worth I ended up moving to a real drive, still solid state, a while ago and it's been working fine ever since.

[–] NinjaTurtle@feddit.online 2 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

If its only the main OS not responding to SSH and the web portal just disappears after a couple of minutes use, then it might be your router is reusing the IP address linked to Proxmox. Proxmox uses a static IP address, so will not change once set up. Your router on the other hand may re use the address if it was never reserved specifically for the Proxmox machine. In other words, two devices are fighting for the same IP address on your router.

This is what happened to me. Took a while to figure it out until someone suggested checking the IPs and Mac addresses on the router. No issue since fixing it on the router. Just reserve the address on the router, reset the device that is using the same address (if you can figure it out), and reset the router. Make sure you are reserving the address for the correct machine by chcking the Mac address.

[–] ProfessorHoover@infosec.pub 1 points 1 week ago

Thanks, I have already reserved the IP address for my host.

[–] possiblylinux127@lemmy.zip 0 points 1 week ago

Physically log into it and check the "vitals" (logs and resource usage)

If I had to speculate I would say that your network card has faulty firmware.