In Proxmox VM you can enlarge you disk quite easily using the user interface. This is typically a fail-safe operation. However, during routine maintenance to enlarge a PBS server attached to an ZFS over iSCSI disk on a TrueNAS server, this didn’t work. Instead we ended up with a crashed operating system and the following was output (spelling errors due to screenshot nature of Apple copy/paste):
[42281.616371] I/D error, dev sda, sector 13171496 op 0X0: (READ) flags 0x80700 phys_seg 1 prio class 2 (42281.622789] I/0 error, dev sda, [42281.622926] sector 9048064 op 0x1: (WRITE) flags 0x3800 phys_seg 1 prio class 2 I/O error, dev sda, sector 9048064 op 0x1: (WRITE) flags 0x3800 phys_seg 1 prio class 2 [42281.623034] Buffer I/0 error on dev dm-1, logical block 0, lost sync page urite [42281.623195] EXT4-fs (dm-1): I/0 error while writing superblock [42281.628408] EXT4-fs (dm-1): Remounting filesystem read-only [42281.686763] EXT4-fs error (device dm-1): ext4_find_entry:1678: inode #1314650: comm tokio-runtime-w: reading directory lblock 0 [42281.742708] Buffer I/D error on dev dm-1, Iogical block o, lost sync page urite [42281.743035] EXT4-fs (dm-1): I/O error while writing superblock
Moral of the story:
Can’t trust live resizing using the Proxmox UI if using TrueNAS iSCSI via Proxmox.