chmod command fails with "Read-only file system"
 

Hi all,

I'm getting a "Read-only file system" error when I try to do the chmod, mkdir, touch, or rm commands. I suspect any file/directory manipulation command will fail with the "Read-only file system" message. I can still cd to any directory, 'ls' still works, I can vi files and view them but I can't modify them. Has anyone run into this problem before or have any ideas?

[root@localhost /> whoami
root
drwxrwxrwx 20 root root 4096 May 31 18:29 www
[root@localhost www> touch testing
touch: cannot touch `testing': Read-only file system

What I was doing when this problem started....
I telnet'd to my linux machine. I created a directory successfully in the root directory. I then did a 'cp -rf /MYDIRECTORY /DESTINATIONDIR' to copy all the contents of one directory to a new directory. This is a big directory and at some point if failed with the "Read-only file system" message. After that my chmod, mkdir and rm commands started failing. So, currently I cannot do any manipulation on any file on my machine or create any new file/directory. Ftp also fails with the error message....
500 OOPS: failed to open xferlog log file:/var/log/xferlog
[root@localhost log> ll xferlog
-rw------- 1 root root 0 Jun 8 04:02 xferlog

Telnet still works.
The 'fsck' command didn't change the behavior at all.

Any help would be greatly appreciated.

Some system info.....
Linux Fedora Core version: 2.6.11-1.1369_FC4

[root@localhost /> df -h -T
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
ext3 37G 9.6G 26G 28% /
/dev/hda1 ext3 99M 9.8M 84M 11% /boot
/dev/shm tmpfs 125M 0 125M 0% /dev/shm

[root@localhost cgi-bin> cat /proc/mounts
rootfs / rootfs rw 0 0
/dev /dev tmpfs rw 0 0
/dev/root / ext3 ro 0 0
none /selinux selinuxfs rw 0 0
/proc /proc proc rw,nodiratime 0 0
/proc/bus/usb /proc/bus/usb usbfs rw 0 0
/sys /sys sysfs rw 0 0
/dev/devpts /dev/pts devpts rw 0 0
/dev/hda1 /boot ext3 rw 0 0
/dev/shm /dev/shm tmpfs rw 0 0
none /proc/sys/fs/binfmt_misc binfmt_misc rw 0 0
sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs rw 0 0
automount(pid2169) /net autofs rw 0 0
automount(pid2133) /misc autofs rw 0 0

There’s your problem.

As root, try
As for how this happened to begin with, I think there is some other issue we are not seeing.

Thanks for the suggestion OSOR but I must be doing something wrong. Here's what I get when I run the 'mount' command as root....

[root@localhost /> pwd
/
[root@localhost etc> mount -o remount,rw /
mount: block device /dev/VolGroup00/LogVol00 is write-protected, mounting read-only

I also did a 'fdisk -l' which gave me no output at all.

Any idea why I am getting that message?

A little more info....

[root@localhost etc> cat fstab
# This file is edited by fstab-sync - see 'man fstab-sync' for details
/dev/VolGroup00/LogVol00 / ext3 defaults 1 1
LABEL=/boot /boot ext3 defaults 1 2
/dev/devpts /dev/pts devpts gid=5,mode=620 0 0
/dev/shm /dev/shm tmpfs defaults 0 0
/dev/proc /proc proc defaults 0 0
/dev/sys /sys sysfs defaults 0 0
/dev/VolGroup00/LogVol01 swap swap defaults 0 0
/dev/fd0 /media/floppy auto pamconsole,exec,noauto,managed 0 0
/dev/hdc /media/cdrecorder auto pamconsole,exec,noauto,managed 0 0

What are the permissions on that block device? Specifically, what does
output? They should be 0660 or similar (at the very least, writable by root). If not, try changing it manually with chmod. If that doesn’t work, you might have to use lvm.

Here is the listing of the LogVol00...

[root@localhost etc> ls -l /dev/VolGroup00/LogVol00
lrwxrwxrwx 1 root root 31 May 12 18:59 /dev/VolGroup00/LogVol00 -> /dev/mapper/VolGroup00-LogVol00

I meant the actual block device, not the link to it. Try

If it's not just a part of your normal configuration, check your system log. Filesystems are sometimes automatically re-mounted as read only if problems with the device are detected.

Ya, the actual file might be more useful than the link. Sorry about that...

[redbird@localhost ~]$ ls -lL /dev/mapper/VolGroup00-LogVol00
brw-rw---- 1 root disk 253, 0 May 12 14:59 /dev/mapper/VolGroup00-LogVol00

I'm looking at the system logs in the /var/log/messages files. Is that what you mean? Anyway, the messages file hasn't been updated since this problem occurred on June 11. The last couple logs are below but they are just session open/close.

Jun 11 17:01:02 localhost crond(pam_unix)[4021]: session opened for user root by (uid=0)
Jun 11 17:01:02 localhost crond(pam_unix)[4021]: session closed for user root
Jun 11 18:01:02 localhost crond(pam_unix)[4505]: session opened for user root by (uid=0)
Jun 11 18:01:02 localhost crond(pam_unix)[4505]: session closed for user root
Jun 11 18:20:23 localhost su(pam_unix)[32543]: session closed for user root
Jun 11 18:21:50 localhost su(pam_unix)[32698]: session closed for user root
Jun 11 18:59:59 localhost su(pam_unix)[5008]: session opened for user root by (uid=500)
Jun 11 19:01:02 localhost crond(pam_unix)[5047]: session opened for user root by (uid=0)
Jun 11 19:01:02 localhost crond(pam_unix)[5047]: session closed for user root
Jun 11 19:09:14 localhost su(pam_unix)[393]: session closed for user root

Well, the device itself seems to be read-write. Perhaps the underlying physical volume has bad permissions. Why else would you get a write-protected message?

Do you know the physical volume(s) which comprise VolGroup00-LogVol00? If not, you should be able to figure it out with lvm. Once you do, check the permissions on those block devices.