Bug 809828

Summary:	tail -f does not work with GPFS file systems
Product:	Red Hat Enterprise Linux 6	Reporter:	Joe Pope <pope_svr4>
Component:	coreutils	Assignee:	Ondrej Vasik <ovasik>
Status:	CLOSED DUPLICATE	QA Contact:	qe-baseos-daemons
Severity:	high	Docs Contact:
Priority:	unspecified
Version:	6.2	CC:	meyering, prc
Target Milestone:	rc
Target Release:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-04-04 13:45:58 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Joe Pope 2012-04-04 13:26:09 UTC

Description of problem: tail -f does not work on GPFS file systems.


Version-Release number of selected component (if applicable):
coreutils-8.4-16.el6.x86_64

How reproducible: Write to a file on hostA within a GPFS file system and try to run "tail -f filename" on hostB. The "tail -f" command on hostB will not produce any output although the file is being updated. The "tail -f" command does work correctly on hostA.


Steps to Reproduce:
1.write to a file within a GPFS file system on hostA
2.tail -f that file on hostB
3.the tail -f command will not produce output on hostB
  
Actual results: The "tail -f" command on hostB will not produce any output although the file is being updated.

Expected results: The tail -f command should work the same on hostA and hostB


Additional info: Searches concerning this issue point to a missing or incorrect magic number in the tail code for GPFS

Comment 1 Jim Meyering 2012-04-04 13:37:04 UTC

Thanks for the report.
For reference, this was fixed in upstream coreutils-8.15.
Here's the corresponding NEWS entry:

  * Noteworthy changes in release 8.15 (2012-01-06) [stable]
    ...
    tail -f no longer tries to use inotify on GPFS or FhGFS file systems
    [you might say this was introduced in coreutils-7.5, along with inotify
     support, but the new magic numbers weren't in the usual places then.]

Here's the commit:

  http://git.sv.gnu.org/cgit/coreutils.git/commit/?id=d191bfe8a688d40

Comment 3 Ondrej Vasik 2012-04-04 13:45:58 UTC

Already tracked and planned for fix in RHEL-6 ... closing DUPLICATE.

*** This bug has been marked as a duplicate of bug 769874 ***