Root filesystem went Read- only mode

[Nigel Wade]

Santosh Kumar wrote:
> Hope you are doing well.
> 
> Root filesystem went Read- only mode on production server. Please help me it
> happens on three different servers and twice on one server within 10days.
> My Database is corrupted. I am using RHEL4 update 7 on some of servers. Disk
> is SAN device.
> 
> There seems to be some problem in writing to control file below. Oracle got
> terminated abruptly.
> Can anyone please look into it.
> 
> 
> ORA-00206: error in writing (block 3, # blocks 1) of control file
> ORA-00202: control file: '/u03/oradata/protect/CONTROL02.CTL'
> ORA-27072: File I/O error

You have I/O errors during write. When this happens the OS re-mounts the filesystem R/O to 
prevent filesystem corruption.

The problem could be anywhere from the interface device driver to the SAN. You say it 
happens on multiple machines, so look for commonality between the failures. Are they all 
mounting the same filesystem, or filsystems from the same SAN?

> 
> Problem solved after reboot the server but its not possible always on
> Production server.

Yes, but it will re-occur if you keep getting I/O errors. You need to find the root cause 
and fix it.

-- 
Nigel Wade, System Administrator, Space Plasma Physics Group,
             University of Leicester, Leicester, LE1 7RH, UK
E-mail :    nmw at ion.le.ac.uk
Phone :     +44 (0)116 2523548, Fax : +44 (0)116 2523555