When hot adding a SCSI device, such as a hard drive, you might have noticed that it doesn’t show in /dev. You can either reboot, which defeats the purpose of hot adding the device, or notify Linux to rescan the SCSI bus. Read more…
Below is a collection of commands for mdadm that I have found useful. Use these at your own risk. Read more…
RAID, which stands for “redundant array of independent” disks provides a way to group disks into one volume and/or provide fault tolerance. There are three way to implement RAID: hardware, a combination of hardware/software, and software only. Read more…
I like to test all the possible scenarios before putting a server into production. One of these tests was whether I could reinstall linux without disturbing the RAID arrays. Unfortunately the Debian and Ubuntu installers do not make this easy. When you reach the partitioning stage it will just show you the physical drives with the linux raid partitions and not the md devices. Here are the steps that worked for me. Read more…