I have found out that XFS doesn’t work well with MBR partition table. I tried XFS since it is recommended for large files and when I formatted 2 of my external HDD with XFS, it refuses to mount after reboot. I already tried xfs_repair but no luck. Both of those 2 drives used MBR so I tried GPT and it mounts without any problems after reboot. I thought XFS is just a problematic filesystem. I hope this helps people who are trying out XFS.