Adding the nobarrier parameter to “/etc/fstab” on a virtual machine causes disk mount failure

[zijiren35]

During the preparation phase of deploying CloudBerry on a virtual machine, modifying the /etc/fstab file and adding the nobarrier parameter will result in the system's inability to mount the disk during startup, leading to boot failure.

[github-actions]

Hi, @zijiren35 welcome!🎊 Thanks for taking the time to point this out.🙌

[my-ship-it]

Thanks for reporting the issue.

Root Cause Analysis

This is a documentation issue, not a code bug:

1. nobarrier is a filesystem mount option that disables write barriers to improve I/O performance.
2. In newer Linux kernels (5.x+), XFS and ext4 have removed support for the nobarrier option. Passing an unrecognized mount option causes the mount to fail.
3. Virtual machine environments typically use newer kernels, making this issue more likely to occur.
4. CloudBerry's deployment documentation (inherited from Greenplum) recommends adding nobarrier to /etc/fstab for disk performance optimization, but this recommendation is
   outdated.

Recommended Fix

The fix should target the deployment documentation:

1. Remove or annotate the nobarrier recommendation — Note that this option is no longer supported on Linux 5.x+ kernels.
2. Provide alternatives — For ext4, barrier=0 may still work. For production environments with BBU-backed RAID controllers, this option can be safely omitted entirely.
3. Add a warning — Advise users to test with mount -o nobarrier first to verify kernel support before writing it to fstab.