Bug 48195 - /var/db/mounttab error on diskless boot
Summary: /var/db/mounttab error on diskless boot
Status: Open
Alias: None
Product: Base System
Classification: Unclassified
Component: conf (show other bugs)
Version: 5.0-CURRENT
Hardware: Any Any
: Normal Affects Only Me
Assignee: freebsd-bugs (Nobody)
Depends on:
Reported: 2003-02-12 02:40 UTC by Dirk-Willem van Gulik
Modified: 2017-12-31 22:36 UTC (History)
0 users

See Also:


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Description Dirk-Willem van Gulik 2003-02-12 02:40:09 UTC
Booting diskless, using ng_rc yields the error below:

	Starting file system checks:
	nfs: can't update /var/db/mounttab for
	+++ mount_md of /var
	+++ populate /var usin

as /var/ does not yet exist.


Possibly a special flag to nfsiod to NOT write
	such or write such to another location which
	may exist.

	Carefull shuffling of the rc order.
	Normal feature of current boot procedure.
Comment 1 Harry Coin 2005-02-14 23:30:22 UTC
I have the same problem on 5.3

I intend a remote (not local memory disk) /etc and remote /var, but the 
initdiskless routine fails the mount_nfs in the 
..serverdiskless-root:/conf/{ip address}/etc/diskless_remount because 
mount_nfs wants to update /var/db/mounttab, which at that point is 
read-only.  Hence it fails.
Comment 2 brooks 2005-02-15 00:08:58 UTC
This is a warning, not an error.  If you're unable to boot, you are
having a different problem.

The real bug is that there is no way to tell mount_* commands to not
write to /var/db/mounttab when it is pointless.

-- Brooks
Comment 3 Harry Coin 2005-02-15 01:37:26 UTC
Thanks very much for this!

I'm able to PXE boot a diskless kernel, but I just keep getting 'Amnesiac' 
and various gripes about unable to update (big list) due to RO root FS.

I will ignore it then and continue to debug my setup.  I'm having problems 
getting the initdiskless diskless_remount to nfs mount a remote etc 
directory based on the ip address.  No need to reply, I'll post again if I 
can't figure it out myself and have a specific error to report.

One helpful item:  Some folks were complaining about getting a 
'setrootbyname failed' error on a diskless machine.  I find that if I just 
don't mention a / directory in my diskless machine's fstab, that error 
doesn't appear.

I wish there was some means to discern whether a bootup message is a 
warning and the command in a script completed to some extent with a notice 
of some failed secondary op (like updating /var/db/mounttab) and yet 
returned an exit code of 0) or whether the message is an error and didn't 

My objective is not to have any memory disks on the diskless machines, 
memory is at a premium while there is plenty of remote disk space (compute 
bound diskless application using lotsa used computers CPU / memory only 
doing a parallel processing thing).

I'm somewhat new to Freebsd so sorry if this seems 'newbie' ish.

Thanks for all the work on Freebsd, I hope to contribute once I get a 
little better at all this.

Comment 4 Eitan Adler freebsd_committer freebsd_triage 2017-12-31 07:59:15 UTC
For bugs matching the following criteria:

Status: In Progress Changed: (is less than) 2014-06-01

Reset to default assignee and clear in-progress tags.

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