Hi,
I did a command-line upgrade of a RHL73 server to Centos 5. It was a bit rocky road, but in the end it was successful.
There's one thing that bugged me. I'm using software RAID1 consisting of /dev/hd{a,c}. No LVM or anything fancy, a number of /dev/mdX partitions, including the root (+/boot).
I'd have preferred to continue using lilo as it works more easily with RAID1 root/boot setups. The deployment guide for Centos5 claims to support RAID1 boot partitions (RHEL4 didn't, and provided a pointer a site in UK which no longer works for more info), it's not clear how exactly a redundant boot block configuraton is achieved with that -- so that if you remove the primary drive, it'll still boot.
Anyone have pointers for this?
[I've gone through a number of sites with various hacks how to install grub on both disks, but I'm not quite sure which ones are valid, and whether those are needed anymore]
.. read on if you're interested about the lilo/mkinitrd problem ..
However, lilo doesn't really work, the root cause as far as I've been able to go is that '/dev/root' isn't recognized and as such not mounted. With grub this works.
The init script in the initrd includes the following (automatically generated): ===8<== echo Creating root device. mkrootdev -t ext3 -o defaults,ro /dev/md0 echo Mounting root filesystem. mount /sysroot ===8<==
And looking at the vast amount of RH bugs about this, it seems this root autodetection has caused significant grief, e.g., https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=197701. However, no bugs on this (or similar) have been filed under RHEL5.
Any thoughts? Anyone run with similar setups?
*) =======8<==== md: autorun DONE .. Creating root device Mounting root filesystem mount: could not find filesystem '/dev/root' Setting up other filesystems Setting up new root fs setuproot: moving /dev failed: no such file or directory no fstab.sys, mounting internal defaults setuproot: error mounting /proc: no such file or dir setuproot: error mounting /sys: no such file or dir ... and finally, a kernel panic. =======8<======
On Sun, 2007-04-22 at 21:40 +0300, Pekka Savola wrote:
Hi,
I did a command-line upgrade of a RHL73 server to Centos 5. It was a bit rocky road, but in the end it was successful.
There's one thing that bugged me. I'm using software RAID1 consisting of /dev/hd{a,c}. No LVM or anything fancy, a number of /dev/mdX partitions, including the root (+/boot).
I'd have preferred to continue using lilo as it works more easily with RAID1 root/boot setups. The deployment guide for Centos5 claims to support RAID1 boot partitions (RHEL4 didn't, and provided a pointer a site in UK which no longer works for more info), it's not clear how exactly a redundant boot block configuraton is achieved with that -- so that if you remove the primary drive, it'll still boot.
Anyone have pointers for this?
[I've gone through a number of sites with various hacks how to install grub on both disks, but I'm not quite sure which ones are valid, and whether those are needed anymore]
This has been touched on several times in the CentOS mailings. Did you also search CentOS? If not, ISTR that there are answers there. For grub, of course. <snip>
HTH -- Bill
Hi,
On Sun, 22 Apr 2007, William L. Maltby wrote:
On Sun, 2007-04-22 at 21:40 +0300, Pekka Savola wrote:
Hi,
I did a command-line upgrade of a RHL73 server to Centos 5. It was a bit rocky road, but in the end it was successful.
There's one thing that bugged me. I'm using software RAID1 consisting of /dev/hd{a,c}. No LVM or anything fancy, a number of /dev/mdX partitions, including the root (+/boot).
I'd have preferred to continue using lilo as it works more easily with RAID1 root/boot setups. The deployment guide for Centos5 claims to support RAID1 boot partitions (RHEL4 didn't, and provided a pointer a site in UK which no longer works for more info), it's not clear how exactly a redundant boot block configuraton is achieved with that -- so that if you remove the primary drive, it'll still boot.
Anyone have pointers for this?
[I've gone through a number of sites with various hacks how to install grub on both disks, but I'm not quite sure which ones are valid, and whether those are needed anymore]
This has been touched on several times in the CentOS mailings. Did you also search CentOS? If not, ISTR that there are answers there. For grub, of course.
<snip>
Yes, though apparently the 'Search' button on the frong page doesn't search mailing lists, it probably should.
Yes, I've done extensive searching. The problem is that there are something like 3-4 ways to achieve the desired end results and those ways apply to various versions of grub.
It's not obvious to me which approach is "The Way" for Centos/RHEL5 (preferably tested and working; if it doesn't work, a bug should be filed). Some mailings seem to hint that it should 'just work' with Centos5 due to changes in Grub, all those postings happened before Centos5/RHEL5 was even released.
For the record, here are IMHO the best links were:
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=160563 http://lists.centos.org/pipermail/centos/2005-May/046668.html http://forums.fedoraforum.org/showthread.php?t=49266 (more detail)
-
Pekka Savola -
William L. Maltby