Recently one of my servers that runs FreeBSD 11.1 keeps hanging on boot. Usually, the 2nd hard reboot will fix it. The root file system on this server is using ZFS and the ZFS pool report it as healthy.

So I’ve been reluctant to do anything about it. Until tonight, when I accidentally list the partition of that drive (ada4):

Ahh.. [CORRUPT] partition table it seems. I think the reason the server can still boot because GPT keeps the partition tables in two places (yes, one of the more reason to use GPT over MBR).

In my case, I fixed the corrupt partition by running this command:

To verify it: