Hello, I have followed the tutorial about converting a running system to RAID 1 but after copying data to the md devices, setting grub and restart I hit a kernel panic: sda1 is boot, sda2 is root and sda3 is swap. The running system is /dev/sda. ========= device-mapper: dm-raid45: initialized v0.2594l Waiting for driver initialization, Scanning and configuring dmraid supported devices Trying to resume from LABEL=SWAP-sda3 Unable to access resume device (LABEL=SWAP-sda3) 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 directory setuproot: error mounting /sys: No such file or directory Switching to new root and running init. unmounting old /dev unmounting old /proc unmounting old /sys switchroot: mount failed: No such file or directory Kernel panic - not syncing: Attempted to kill init! ================= I would like to mention that the only step that I missed was the "update-initramfs -u" which returned a "command not found" error I and didn't know what to replace it with. A little help would be welcome! Thanks and regards!
Hi, Right...sorry about that. The distro is CentOS 5.4 / 32 bit. [root@localhost ~]# cat /etc/fstab /dev/md1 / ext3 defaults 0 1 /dev/md0 /boot ext3 defaults 0 2 /dev/md2 none swap sw 0 0 tmpfs /dev/shm tmpfs defaults 0 0 devpts /dev/pts devpts gid=5,mode=620 0 0 sysfs /sys sysfs defaults 0 0 proc /proc proc defaults 0 0 [root@localhost ~]# cat /boot/grub/menu.lst # grub.conf generated by anaconda # # Note that you do not have to rerun grub after making changes to this file # NOTICE: You have a /boot partition. This means that # all kernel and initrd paths are relative to /boot/, eg. # root (hd0,0) # kernel /vmlinuz-version ro root=/dev/sda2 # initrd /initrd-version.img boot=/dev/sdb default=0 fallback 1 timeout=5 splashimage=(hd0,0)/grub/splash.xpm.gz hiddenmenu title RAID root (hd1,0) kernel /vmlinuz-2.6.18-164.el5 root=/dev/md1 ro initrd /initrd-2.6.18-164.el5.img savedefault title CentOS (2.6.18-164.el5PAE) root (hd0,0) kernel /vmlinuz-2.6.18-164.el5PAE ro root=LABEL=/1 initrd /initrd-2.6.18-164.el5PAE.img title CentOS-base (2.6.18-164.el5) root (hd0,0) kernel /vmlinuz-2.6.18-164.el5 ro root=LABEL=/1 initrd /initrd-2.6.18-164.el5.img Thanks for replying! Best regards!
Please try this guide instead: http://www.howtoforge.com/how-to-se...ing-system-incl-grub-configuration-centos-5.3 The command to create a new initrd is mkinitrd on CentOS.
Quote falko "Please try this guide instead: http://www.howtoforge.com/how-to-se...ing-system-incl-grub-configuration-centos-5.3 The command to create a new initrd is mkinitrd on CentOS." Hi, thanks! I have tried to follow that tutorial and used mkinitrd a couple of days ago and it worked to a point. Unfortunately /dev/sda2 (the initial root partition) is indicated as "device busy" because if I put root=/dev/md1 in grub.conf on the kernel line it will throws me again "kernel panic" so I have to boot with root=LABEL=/1 in the kernel line in grub.conf. I have recompiled initrd and I believe it added raid support: [root@localhost boot]# mkinitrd -v -f --preload=raid1 --with=raid1 /boot/initrd-2.6.18-164.el5PAE.img 2.6.18-164.el5PAE ....... Adding module raid1 Adding module ehci-hcd Adding module ohci-hcd Adding module uhci-hcd Adding module jbd Adding module ext3 Adding module scsi_mod Adding module sd_mod Adding module libata Adding module ahci Adding module dm-mem-cache Adding module dm-mod Adding module dm-log Adding module dm-region_hash Adding module dm-message Adding module dm-raid45 I am choosing the second option (PAE) in grub at boot time and this is my grub.conf: [root@localhost boot]# cat grub/grub.conf # grub.conf generated by anaconda # # Note that you do not have to rerun grub after making changes to this file # NOTICE: You have a /boot partition. This means that # all kernel and initrd paths are relative to /boot/, eg. # root (hd0,0) # kernel /vmlinuz-version ro root=/dev/sda2 # initrd /initrd-version.img boot=/dev/sdb default=0 fallback 1 timeout=5 splashimage=(hd0,0)/grub/splash.xpm.gz hiddenmenu title RAID root (hd1,0) kernel /vmlinuz-2.6.18-164.el5 root=/dev/md1 ro hdb=60801,255,63 initrd /initrd-2.6.18-164.el5-2.img savedefault title CentOS (2.6.18-164.el5PAE) root (hd1,0) kernel /vmlinuz-2.6.18-164.el5PAE ro root=/dev/md1 initrd /initrd-2.6.18-164.el5PAE.img title CentOS-base (2.6.18-164.el5) root (hd0,0) kernel /vmlinuz-2.6.18-164.el5 ro root=LABEL=/1 initrd /initrd-2.6.18-164.el5.img When I boot with root=LABEL=/1 it boots normally but with root=/dev/md1 it throws me a kernel panic. So I don't seem to be able to boot directly from a RAID mount point although I have compiled it into initrd. But if I boot from non-raid (sda2), raid is active after boot: [root@localhost boot]# cat /proc/mdstat Personalities : [raid1] md1 : active raid1 sdb2[1] 51199040 blocks [2/1] [_U] md2 : active raid1 sdb3[1] 4096448 blocks [2/1] [_U] md0 : active raid1 sdb1[1] 104320 blocks [2/1] [_U] unused devices: <none> I am really lost here. If you can please point me into the right direction. Thanks!
As to "root=LABEL=/1": [root@localhost by-label]# ls -l /dev/disk/by-label total 0 lrwxrwxrwx 1 root root 10 Feb 11 21:10 1 -> ../../sda2 And a mount: [root@localhost /]# mount /dev/md1 on / type ext3 (rw) proc on /proc type proc (rw) sysfs on /sys type sysfs (rw) devpts on /dev/pts type devpts (rw,gid=5,mode=620) /dev/md0 on /boot type ext3 (rw) tmpfs on /dev/shm type tmpfs (rw) none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw) sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
After quite a lot of shooting in the dark I believe I have nailed it down (kind of). When I was booting option no 1 it was giving me some error when loading X11 and it was returning me to the login form. I have tried to login on console ctrl+alt+f2 but again after entering right credentials it was redirecting me to the login form. After a little bit of googling I found out it might be due to selinux so I booted with selinux=0 and right on cue it worked. I have added sda to the raid matrix and after sync even option no 2 started to work (PAE). So I am not sure why option no 2 was hitting a kernel panic while booting with root=/dev/md1 while option no 1 didn't...the only difference was the kernel version (normal vs PAE) which I didn't touch and the ramdisc image (which I compiled with the same options). If anyone has any theory as to why this was happening I am more than interested to find out. Anyway...thanks for answering Falko!
