Re: Converting a non Raid redhat system to a Linux system with disk mirroring
Date: Tue, 30 Mar 2004 14:19:34 +0100
ddl <email@example.com> wrote:
> I am using RedHat 7.3 as my mail server with kernel 2.4.20-28.7. I would
> like to install RAID mirroring on it without formatting the whole system.
Yes. It's straightforward - but not easy - once you understand what's
required and what's going on. If you have *any* doubts then don't try
it on a system that you can't afford to trash.
> It always says that resize2fs cannot be used on an already mounted
> filesystem. I tried to copy the resize2fs to /sbin and then unmount the root
> filesystem. The resize of the
> root filesystem was then successful but after I rebooted the system I
> received a kernel panic error saying something like could not read
You've quite probably trashed this system by now, then. Unfortunately.
> Please advise if anyone has done a successful RAID convertion (without
Yes. I've done it. I didn't need to resize anything, so I'm puzzled why
should have been directed to do so.
If you google through the various linux groups, including uk.comp.os.linux
and comp.os.linux.misc you'll find several threads discussing this same
question. At least two of them (IIRC) I have contributed to, so I'm
going to refrain from spouting the same details here.
* Set up RAID on new disk, with current disk marked as "faulty" in the configuration
* Copy all existing files across to new RAID partitions
* Fix up new partition types to RAID-auto-detect
* Build boot floppy. You will need it
* Reconfigure lilo/grub and /etc/fstab to use new RAID partitions
* If that doesn't work use your boot floppy to get back to the original and recheck what you've done
* Mark the old partitions as replaced and RAID hot-add them to the RAID arrays