Bug 2117355

Summary: Add additional documentation for fstab
Product: Red Hat Enterprise Linux 8 Reporter: Christopher Bradshaw <cbradsha>
Component: util-linuxAssignee: Karel Zak <kzak>
Status: MODIFIED --- QA Contact: Radka Brychtova <rskvaril>
Severity: low Docs Contact:
Priority: medium    
Version: 8.0CC: agk, heinzm, jbrassow, jmagrini, msnitzer, prajnoha, rmadhuso, zkabelac
Target Milestone: rcKeywords: Documentation, FutureFeature, Triaged
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: util-linux-2.32.1-43.el8 Doc Type: Enhancement
Doc Text:
Story Points: ---
Clone Of:
: 2209267 (view as bug list) Environment:
Last Closed: 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:
Bug Depends On:    
Bug Blocks: 2209267    

Description Christopher Bradshaw 2022-08-10 18:01:52 UTC 
Description of problem:

Filesystems(commented in fstab) are getting mounted after activating the volume group or logical volume via vgchange or lvchange (due to systemd unit files not updating). 

This is a request for additional documentation in the manual pages and a clearer KCS or Article (easier to find online). 

Version-Release number of selected component (if applicable):

Red Hat Enterprise Linux 7

How reproducible:

Every time.

Steps to Reproduce:

1.) Umount and comment out a filesystem:

   $ umount  /mnt/test
   $ grep test /etc/fstab
     #/dev/mapper/vgtest-lvtest  /mnt/test   xfs defaults,nodev,nobarrier 0  0

2.) Deactivate Volume Group and then Activate Volume Group:

   $ vgchange -an vgtest
     0 logical volume(s) in volume group "vgtest" now active

     0 logical volume(s) in volume group "vgtest" now active
   $ vgchange -ay vgtest
     4 logical volume(s) in volume group "vgtest" now active

Actual results:

The commented out filesystem is still automatically mounted (due to systemd unit file not being updated):

   $ df -k | grep lvtest
    /dev/mapper/vgtest-lvtest    2086912   32944   2053968   2% /mnt/test


Expected results:

Customer expects the commented filesystem to not be automatically mounted when activating the Volume Group. The customer understands that this is due to systemd unit files not being updated without reboot or systemctl daemon-reload. 

This is really a request for additional documentation by Red Hat (i.e. manual pages updated for vgchange/lvchange/systemd). 


Additional info:

Customer is asking for clearer documentation in the manual pages for vgchange, lvchange, lvm, and systemd. Customer now understand that this is due to the systemd unit not being updated - and the need to run:

   $ systemctl daemon-reload

Reference Red Hat KCS:

   https://access.redhat.com/solutions/3059631
Comment 3 Christopher Bradshaw 2022-08-12 17:54:15 UTC 
NOTE: I submitted this request for additional documentation for RHEL 7.* but think this would be a good addition for all versions >RHEL 7.0 (using systemd).
Comment 6 Karel Zak 2023-05-23 09:38:59 UTC 
Good idea; I have added to the upstream fstab.5 hint about systemd.
https://github.com/util-linux/util-linux/commit/9105d3cdd819a499f5029d1009952acf6f51b7d9

We can backport it to RHEL-8 and RHEL-9 (for RHEL-7 it's probably overkill to create errata for a man page change)