Bug 747552

Summary:	rpc_pipefs is not re-mounted properly when using nfs root.
Product:	Red Hat Enterprise Linux 6	Reporter:	Ondrej Valousek <ondrejv>
Component:	initscripts	Assignee:	Lukáš Nykrýn <lnykryn>
Status:	CLOSED ERRATA	QA Contact:	Jan Ščotka <jscotka>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	6.1	CC:	harald, jrieden, lnykryn, psklenar, rvokal, torel, vpavlin
Target Milestone:	rc
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	initscripts-9.03.43-1.el6	Doc Type:	Bug Fix
Doc Text:	This allows to use root on NFS and reaonly root. But this setup is not supported.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2014-10-14 06:26:58 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 Ondrej Valousek 2011-10-20 09:35:26 UTC

Description of problem:
I am booting a diskless RHEL-6 environment using dracut this way:
[victim@data ~]$ cat /proc/cmdline
initrd=rhel6-ws-boot/initramfs.img console=ttyS0,115200 console=tty0
root=nfs4:192.168.60.50:/vol/vol1/OS/rhel6/root crashkernel=256M@16M nomodeset
vesa BOOT_IMAGE=rhel6-ws-boot/vmlinuz
The system boots up correctly with / mounted via nfs4 but rpc_pipefs is not
mounted correctly to /var/lib/nfs/rpc_pipefs.

Strangely enough, it "looks and feels" that it is mounted:

[root@data ~]# mount | grep rpc
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw,relatime)

... but is not really:

[root@data ~]# umount /var/lib/nfs/rpc_pipefs
umount: /var/lib/nfs/rpc_pipefs not mounted

and no NFS4 ID mapping is working as well. After re-mounting manually this way:

[root@data ~]# mount -t rpc_pipefs sunrpc /var/lib/nfs/rpc_pipefs

and restarting rpc.idmapd, the ID mapping starts working again.

Version-Release number of selected component (if applicable):
[ondrejv@data ~]$ rpm -qi dracut
Name        : dracut                       Relocations: (not relocatable)
Version     : 004                               Vendor: Red Hat, Inc.
Release     : 33.2.el6_0                    Build Date: 

How reproducible:
always

Comment 1 Ondrej Valousek 2011-10-20 09:41:52 UTC

I originaly believed it is a dracut problem (see bug 701309), but it is obliously not.
The script /etc/rc.d/rc.sysinit goes through the /etc/rwtab and mount /var to tmpfs thus making the rpc_pipefs filesystem no longer accessible.

So I believe we should handle this in rc.sysinit script - after mounting all the stateless/persistent state files and directories, we should also make sure that /var/lib/nfs/rpc_pipefs is mounted correctly.

Comment 5 RHEL Program Management 2012-05-03 05:32:23 UTC

Since RHEL 6.3 External Beta has begun, and this bug remains
unresolved, it has been rejected as it is not proposed as
exception or blocker.

Red Hat invites you to ask your support representative to
propose this request, if appropriate and relevant, in the
next release of Red Hat Enterprise Linux.

Comment 6 Harald Hoyer 2013-04-03 10:22:15 UTC

Well, IIRC we don't support root on NFS in RHEL officially.

But yes, you have a point here.

We could setup the new /var temporarily on $tmpdir and mount move over all mounts in /var to $tmpdir and then mount move $tmpdir to /var.

Comment 7 Václav Pavlín 2013-05-29 08:45:12 UTC

Fix commited upstream -> 718550312d46b9ef7b9aaa2d7ba020273a17adf7

Comment 9 Tore H. Larsen 2014-04-01 09:37:42 UTC

cc

Comment 11 Lukáš Nykrýn 2014-06-06 13:45:11 UTC

https://git.fedorahosted.org/cgit/initscripts.git/commit/?h=rhel6-branch&id=05f521938fc56308077f0f58a38ebe3a0c7ffaad

Comment 14 errata-xmlrpc 2014-10-14 06:26:58 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2014-1448.html