Ubuntu – “mounting ext3 file system using the ext4 subsystem” – what does this mean exactly

ext3ext4Ubuntu

I am running Ubuntu 16.04.1, and my main partition is formatted as ext3. Checking syslog I see : mounting ext3 file system using the ext4 subsystem does this mean that the partition is mounted as ext4?

GParted and blkid show ext3.

Best Answer

No, the partition is mounted as ext3; it's just that ext3 file systems are handled by the ext4 driver nowadays, with the message you see when they're mounted. There used to be a separate ext3 driver, but it was dropped when the ext4 driver had proven itself reliable. The ext4 driver checks that file systems mounted as ext3 only use ext3 features, so that they remain compatible with the old ext3 driver.