Bug 484112

Summary:	USB mount via /etc/fstab doesn't work at system startup
Product:	[Fedora] Fedora	Reporter:	Frank van Maarseveen <frankvm>
Component:	initscripts	Assignee:	Bill Nottingham <notting>
Status:	CLOSED DUPLICATE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	medium	Docs Contact:
Priority:	low
Version:	10	CC:	frankvm, notting, rhladik, rvokal
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2009-03-20 21:06:27 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Frank van Maarseveen 2009-02-04 20:51:17 UTC

Description of problem:
Permanent UUID= based mount of an USB storage device via /etc/fstab
mostly doesn't work due to a race between mount and kernel+udev in
/etc/rc.sysinit.

/etc/rc.sysinit calls /sbin/start_udev. Before, the kernel knows the particular
USB storage device according to /proc/partitions but afterwards not (!). It
takes seconds for the device to appear again in /proc/partitions and probably
a bit longer for udev to populate /dev accordingly. This causes a mount -a
around line 666 in /etc/rc.sysinit to fail.


Version-Release number of selected component (if applicable):
Using F10, initscripts-8.86-1.i386, udev-127-3.fc10.i386, kernel 2.6.27.13
(no modules but this is probably not an issue). Except for the home brew
(stock) kernel all up-to-date for F10.


How reproducible:
3 out of 4 times the USB storage device doesn't get mounted and "mount -a"
around line 666 in /etc/rc.sysinit correctly complains that there is no
/dev/sd* (verified with strace).


Steps to Reproduce:
Boot the system with an USB storage device present and preconfigured
in /etc/fstab. If mount happens to succeed everytime then compare
/proc/partition output before and after the /sbin/start_udev command
in /etc/rc.sysinit (it is a race condition after all).


Actual results:


Expected results:


Additional info:
The work-around is to wrap the /sbin/start_udev command inside
/etc/rc.sysinit: before, remember the devices present in
/proc/partitions. Afterwards, wait until they are all present in
/dev. This results in a considerable delay however.

Comment 1 Bill Nottingham 2009-02-04 21:37:06 UTC

/proc/partitions actually has devices *detach* while in start_udev? That shouldn't happen.

Comment 2 Bill Nottingham 2009-03-20 21:06:27 UTC

I believe this bug is a duplicate of another one already filed.b

*** This bug has been marked as a duplicate of bug 481470 ***

Comment 3 Radek Hladik 2009-11-02 16:03:02 UTC

I am expiriencing the same problem on F11 (64bit). Initscripts is version initscripts-8.95-1.x86_64 that should fix the problem according to duplicate bug. However it still fails on almost every boot. 

FSTAB line:
UUID=9ebdd657-f31b-43db-85aa-8185e60ad3ea /boot ext3    defaults 1 0

If I change the last 0 to 1 to force fsck on boot the system fails to boot. On console one can see the prompt for root password and a few moments after message that USB device has been found. With the zero system boots but if it would not be /boot partition it could make problems during service startup (the USB device us sometimes found even after complete startup).