buffer I/O error sda1 (in guest)


Well-Known Member
Nov 5, 2014
A big problem appeared today.

1. Those errors appear in console:


2. It is a LVM-Thin device, that Proxmox shows as 100% usage:

3. Device information shows 325Gb (actually it is a 300Gb WD Velociraptor RAID-1 HDD):

4. lvs -a output from the host, shows 100% of some 185 Gb "data" disk (it showld be 300Gb):

5. df from guest:

I do not understand why Proxmox shows 185Gb LVM? Why are those errors? Cause of 100% full LVM?

What should I do?

Could you please tell me what I have to do right now to get the server back online?
I thought your disk is in real full, so you have 300GB and currently you have with data, swap and PVE root around 262GB available.

You can try to delete files innert the VM or use fstrim (only possible if you have SCSI and Discard enabled on the virtual disk). Otherwise you can try to reduce the PVE root volume and add this free space to data volume. You can delete the swap volume too and add swap afterwards as a file or a smaller volume. But at this point, I can only repeat me, you have to understand LVM.

Or you expand it with additional disks or bigger one.


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