Ceph: A file created as a non-root user on one host, appears empty when read on another host (0 size, cat returns nothing) (root_squash)

Solution Verified - Updated -

Environment

Red Hat Ceph Storage (RHCS) 5.x
Red Hat Ceph Storage (RHCS) 6.x
Red Hat Ceph Storage (RHCS) 7.x

Issue

CephFS: With root_squash client capability enabled, a file created as a non-root user on one host, appears empty when read on another host
(0 size, cat returns nothing)

Steps to reproduce:

$ ssh user@host1 'date > /mnt/ceph1-npx/stress-test/user/XXX'
$ ssh user@host2 'cat /mnt/ceph1-npx/stress-test/user/XXX'
(no output)

Resolution

  • The issue is resolved in RHCS 6.1z9 and higher, see artifacts below.
  • Once released, this artifacts will be updated with the Errata.
  • As a workaround, the Root Squash feature can be disabled.
  • See Section 3.3 of the File System Guide for steps to enable/disable Root Squash.

Root Cause

A defect in the RHCS MDS code introduced in RHCS 5.x.

Artifacts

Product/Version Related BZ/Jira Errata Fixed Version
GitHub GitHub 47506 N/A N/A
GitHub GitHub 48027 N/A N/A
Upstream Ceph Tracker 56067 N/A N/A
Upstream Ceph Tracker 57154 N/A N/A
RHCS/6.1 Bugzilla 2137693 Errata TBD 6.1z10 - 6.1.10

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