What does "mapping=identity" mean in /etc/exports?
by Greg Scott
Hello -
I'm migrating an old NFS server to newer hardware. /etc/exports in the old environment looks like this:
/shares/IMSHCS01 *(rw,insecure,sync,no_root_squash,all_squash,mapping=identity,anonuid=0,anongid=0
So the old system is exporting the directory, /shares/IMSHCS01 to anyone and everyone who wants to connect, with a bunch of switches essentially making it wide open.
Wonderful.
But on the new system, when I set up /etc/exports the same way, I get this error:
[root@nfs2013 etc]# exportfs -av
exportfs: /etc/exports:1: unknown keyword "mapping=identity"
[root@nfs2013 etc]#
Getting rid of "mapping=identity", my shared directory exports just fine.
I can find no mention of "mapping=identity" in any man pages, but several google references show this option in pasted-in copies of /etc/exports files. My hunch is, this is an obsolete option and no longer supported - but what did it do in case my new server needs to behave the same way the old server behaved?
Thanks
- Greg Scott
11 years, 3 months
Re: F18 grub hang with blinking cursor after kernel update [SOLVED]
by Mike Zingale
Turns out that if you update the kernel with an external USB disk plugged
in, grub gets hosed. When I originally did the system yum update I had a
disk plugged in, that broke it the first time. I still had that external
disk plugged in for each attempt at rescue/grub2 reinstall. Finally it
dawned on me to try it without the external disk, and booting from the
install cd, rescue mode, and reinstalling grub fixed it all.
Weird bug.
11 years, 3 months
fedora / mounting point
by Patrick Dupre
Hello,
In Fedora 18 I am trying to install the / (root partition) on my
own partition, but it seems impossible?
Am correct?
"You must create a new filesystem on the root device"
Can I change later?
Thank.
--
======================================================================
Patrick DUPRÉ | | email: pdupre(a)kegtux.org
Laboratoire de Physico-Chimie de l'Atmosphère
Université du Littoral-Côte d'Opale | |
Tel. | | Fax: 03 28 65 82 44
189A, avenue Maurice Schumann | | 59140 Dunkerque, France
======================================================================
11 years, 3 months
mount --move in fedora 18
by Norman Gaywood
When using fedora and ltspfs, ltsp clients want to fuse mount their USB
drives onto the system into the /media directory. This mostly works except
for the last step of move mounting into the /media.
The part that fails is the equivalent of the last line in these steps:
mkdir -p /tmp/testing
cd /tmp/testing/
mkdir -p foo bar
mount -t tmpfs tmpfs foo/
mount --move foo bar/
The last step will give the error:
mount: wrong fs type, bad option, bad superblock on /tmp/testing/foo,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
This worked (the mount --move) in Fedora 16 (without sandbox installed) and
Fedora 17. But not in fedora 18.
When the bug appeared briefly in F16, this bug:
https://bugzilla.redhat.com/show_bug.cgi?id=838447
was logged. As noted there removing sandbox fixed the problem.
F18 seems to make use of pam_sandbox which is probably want is stopping the
mount --move this time.
So how do I configure/remove pam_sandbox so the mounts will work again?
--
Norman Gaywood, Computer Systems Officer
University of New England, Armidale,
NSW 2351, Australia
ngaywood(a)une.edu.au Phone: +61 (0)2 6773 2412
http://mcs.une.edu.au/~norm Fax: +61 (0)2 6773 3312
Please avoid sending me Word or Power Point attachments.
See http://www.gnu.org/philosophy/no-word-attachments.html
11 years, 3 months
Re: NFS Client: Backup preparation problem[solved]
by Amit Karpe
On Fri, Mar 1, 2013 at 10:46 AM, Amit Karpe <amitkarpe(a)gmail.com> wrote:
>
>
> On Fri, Mar 1, 2013 at 2:35 AM, Michael E. Maher <
> michael(a)maheronline.co.uk> wrote:
>
>> Hi Amit,
>>
>> On Thu, 2013-02-28 at 17:39 +0800, Amit Karpe wrote:
>> >
>> > If I used no_root_squash in /etc/exports on server I can access
>> > directory without problem.
>> > /disk12 172.21.123.219(rw,sync,no_root_squash)
>> >
>> > What can be the problem ?
>> >
>>
>> You have kind of answered your own question here. If you need root
>> access to the files from the client, you will need the 'no_root_squash'.
>> All that option does is honour your clients root user over the NFS share
>> (not great for security but I don't know your set up details).
>>
>> Other than that you'd have to manage the users on both systems, to be
>> the same name/uid/gid etc.. and do everything as a non-root user (better
>> for security).
>>
>> Take a look at this link[0] and hopefully that should clear it all up.
>>
>>
>> Thanks,
>> Michael
>>
>>
>> [0]
>> http://www.troubleshooters.com/linux/nfs.htm#_If_it_mounts_but_cant_access
>>
>>
>>
> Michael,
> In following situation if I access as root or non-root, I am facing same
> "Permission denied" error.
> So the problem is just not with root but all users.
>
> client# ls -l /borneo4
> ls: cannot access /borneo4/test-dir: Permission denied
> ?????????? ? ? ? ? ? test-dir
> client# su - eos
> client$ ls -lh /borneo4/
> ls: cannot access /borneo4/test-dir: Permission denied
> total 0
> ?????????? ? ? ? ? ? test-dir
>
>
>
> And on server side I am ready change file permissions. By
> changing ownership of directory will solve this problem without using
> no_root_squash ?
>
>
Finally I solved this problem by just changing permission on server
directory.
server# chmod o+x /borneo4
Now my client can access without any problem.
Thank You, Michael.
11 years, 3 months
NFS Client: Backup preparation problem
by Amit Karpe
Hi All,
I am not able to access particular directory on client which is mounted
using NFS.
client# ls -l /mnt/tmp
ls: cannot access /mnt/tmp/del: Permission denied
total 0
?????????? ? ? ? ? ? del
I have following disk on server.
server# ls -ld /disk12
drwxrwxr-- 3 root root 4096 2013-02-28 15:53 /disk12
Entry in /etc/exports on server.
/disk12 172.21.123.219(rw,sync)
On client
Entry in /etc/fstab
172.21.123.225:/disk12 /mnt/tmp nfs
fsc,rsize=32768,wsize=40960,rw 0 0
If I used no_root_squash in /etc/exports on server I can access directory
without problem.
/disk12 172.21.123.219(rw,sync,no_root_squash)
What can be the problem ?
11 years, 3 months