filesystem remounted as read only

[Andreas Dilger]

On Nov 03, 2005  01:35 +0000, Kent Tong wrote:
> I'm running kernel 2.6.8-15, lvm2 v2.01.04-5 and acl v2.2.23-1 on a 
> Sunblade 100 (sparc). In a few months we have experienced for several 
> times that an ext3 filesystem is remounted as read-only (this is due 
> to the option "errors=remount-ro" in /etc/fstab). Sometimes there is 
> no error in log files but sometimes we see:
> 
> kernel: init_special_inode: bogus i_mode (3016)
> kernel: init_special_inode: bogus i_mode (3125)
> kernel: init_special_inode: bogus i_mode (3144)
> kernel: init_special_inode: bogus i_mode (3231)
> kernel: init_special_inode: bogus i_mode (3423)
> kernel: init_special_inode: bogus i_mode (3452)
> 
> In the former case (no error in the logs), then running fsck will find 
> no error. In the latter case, it may find some errors and fix them.
> 
> I've run smartmontools to check the disks but no errors are found.
> 
> I've run "fsck -c" to look up bad blocks but nothing is found.
> 
> What else can I do to troubleshoot the problem? In particular, the
> most strange is if it is remounting as read-only, why there is no
> error in the logs? Could remounting as read-only prevent it from
> writing to the logs?

Remounting read-only should only happen in the context of "ext3_error".
The init_special_inode() code does not return an error to the caller
so in some cases this error may go unnoticed.

In cases where there is a runtime error but no problem is found on
disk, it is usually a memory error.  It is also possible there is
a cable error or similar.

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.