I've a machine that has the following hardware ASRock A770 CrossFire Motherboard with a AMD Phenom(tm) II X6 1055T Processor (6 core); 24 GB RAM; 6 - Western Digital hard drives (4 - 1 TB and 2 - 2TB). Under CentOS 6 the hard drives are named /dev/sda through /dev/sdf when I installed CentOS 6 using software RAID-1 and RAID-10 the boot loader demanded it be installed on /dev/sdf. The primary RAID-1 devices (/dev/md0; /dev/md1; /dev/md2) house /boot; vg_opsys; vg_swap. They are made up of /dev/md0 = /dev/sdc1 | /dev/sdf1 /dev/md1 = /dev/sdc2 | /dev/sdf2 /dev/md2 = /dev/sdc3 | /dev/sdf3. The reason for this post is to find out how to replace /dev/sdf (it is showing as bad during boot and showing errors in webmin). Under CentOS 7 - how do I install the boot loader on /dev/sdc so the machine will boot to replace /dev/sdf? Is it possible to boot using /dev/md0 and how do I do that? Can I copy the partition structure from /dev/sdc to /dev/sdf using the process located here on HowtoForge? Is there a documented way to do this the I can use as a normal process? TIA Gene
Read the docs for the software you used for setting up RAID. Those should tell you how to replace a failed disk. Why both 6 and 7 of CentOS? Do you have two computes with failed disk? Anyway, answers to your questions should be available in the docs for the RAID system used.
I only use CentOS 6 to configure the drives - I am use to /boot being /dev/md0 not /dev/md126 or something similar. Once the CentOS 6 minimal install has been completed I install CentOS 7. I also mentioned CentOS 6 because during that install it placed the boot loader on /dev/sdf. But CentOS 7 doesn't tell you where it installs boot loader - I'm guessing it places it on /dev/sdf because that's the first BIOS drive (?). TIA Gene
I do not use CentOS, but Debian and Ubuntu have changed the way devices are named between releases. The new system should keep name of device same between reboots, so it is better. But I would say it is wrong to assume device names in Centos 7 are the same as in CentOS 6. Not knowing CentOS I may be wrong, but I would be suprised if it is not possible to install boot loader to disk you choose.
