> CentOS List wrote: >>> CentOS List wrote: >>>>>>>> I am running raid 1 on a centos 4.4. One of the harddisk (sda1) >>>>>>>> failed. How can i carry on running the server using only sda2? >>>>>>> >>>>>>> Generate a grub floppy and use that to load the grub menu from the >>>>>>> sdb (probably now sda) disk. >>>>>>> >>>>>>> If you are really talking about sda1 and sda2, those are >>>>>>> partitions on the same disk. >>>>>> >>>>>> Is there a detail step by step howto? The raid 1 has no LVM. just >>>>>> md0, md1 and md2. md0 is /boot, md1 is swap and md2 is the storage. >>>>>> I had replace sba with a new disk. I tried to boot up and it says >>>>>> kernel panic. How am i going to reconstruct the raid and sync sdb >>>>>> to sda? >>>>> >>>>> It might be easier to swap the old sdb into the sda position so >>>>> you'll boot from it, but you should also be able to boot the install >>>>> cd with >>>> >>>> If swapped and booted, and got a kernel panic error. >>> >>>>> 'linux rescue' at the boot prompt, let it detect and mount your >>>>> system (which will be the 'broken' raid devices with their single >>>>> members), >>>> >>>> If i use linux rescue, The 3 mds I created are gone. /cat >>>> /proc/mdstat says Personalitlies: [raid0] [raid1] [raid5] [raid6], no >>>> longer Personalities : [raid1] >>> >>> Perhaps your raid wasn't really working the way you thought before. >>> From the rescue boot, does fdisk show the 3 partitions on the old disk >>> with type 'fd'? Can you mount the old /boot and / partitions >>> somewhere by hand? You should be able to do this with the /dev/sda1 >>> and /dev/sda3 device names if the md devices aren't detected at boot. >> >> cat /proc/partitions still shows me the 3 partitions. > > Does fdisk say that they are type 'fd'(raid autodetect)? Yes. There are 3 fd (raid autodetect) >> I actually copied >> /boot to the "replaced disk" and it is able to boot up, but without any >> filesystem, so i guess the boot is still intact. So do i need to mount >> /boot and /? > > If you can get the original partitions to be detected as their md > devices you should fdisk matching partitions on the replacement disk, > then 'mdadm --add ...' to add them and they will automatically sync up. So I just have to manually add md to the 3 partitions? regards