Towards the end of last year, I introduced Proxmox into my Homelab. I’m using it to host various services on VMs and LXC containers. In my setup, I have two external SSDs providing storage, these are connected to my Proxmox node via USB 3.0. However, recently I was experiencing issues with the SSDs suddenly disconnecting from the Proxmox node!
This was very frustrating because the VM filesystems that were on these SSDs were becoming corrupted! 😱
This issue was happening on Proxmox 8.1.3 and kernel version 6.5.11-7-pve.
Troubleshooting
On Proxmox, you can check the system logs via the GUI by navigating to the node, and under System is syslog. It’s also possible via the journalctl command on the Proxmox node itself.
Upon inspecting the Proxmox node logs, I couldn’t see any indication as to why the disconnects were happening. I could see the disconnect event occurring but prior to that, everything was normal. Here’s an example of the kernel logs:
Feb 09 22:11:04 proxmox01 kernel: usb 2-1: USB disconnect, device number 17
Feb 09 22:11:04 proxmox01 kernel: sd 4:0:0:0: [sdb] Synchronizing SCSI cache
Feb 09 22:11:04 proxmox01 kernel: sd 4:0:0:0: [sdb] Synchronize Cache(10) failed: Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK
I checked the SMART status of the SSDs and they were healthy, I tried different USB ports on the Proxmox node, swapping the USB 3.0 to SATA cables, nothing seemed to help 😕
The Fix
After some research, I found that the issue may have been related to USB power saving settings. After a certain period of time, the OS places USB devices in a low-power state to save power, which was causing the USB drives to disconnect! 🤯
To resolve the problem, with some help from our good friend ChatGPT, I permanently disabled the USB power saving settings by adding usbcore.autosuspend=-1 to the GRUB kernel boot options in /etc/default/grub:
GRUB_CMDLINE_LINUX_DEFAULT="quiet usbcore.autosuspend=-1"
Then, applying the changes and rebooting the Proxmox node:
update-grub
reboot
After making these changes, I haven’t experienced any further disconnects! 🎉 🥳