Read-only file system

The mount stopped accepting writes

EROFS comes from the filesystem, not from permissions.

findmnt -no OPTIONS /var/lib/thing
mount | grep ' / '

A filesystem remounted ro after an I/O error, a read-only container mount, or an immutable attribute set on the directory.

lsattr -d /var/lib/thing

Attribute i blocks writes regardless of mount options and survives a remount.

Scope: failure mode: A mount that stopped accepting writes.

CliHelper documents failure modes of third-party command line tools. No software is stored or distributed here.