Raid monitor linux
However, you do have to get the partitioning right.
RAID MONITOR LINUX SOFTWARE
The software RAID operates at a level below the filesystem, so you do not need to re-create any filesystems. If this system does not use Microway’s default partitioning (partitions 1, 5, 6, 7, 8, 9, 10) you will need to adjust the commands. I’m assuming that /dev/sda and /dev/sdb are the two drives currently running. Microway customers should contact tech support with any questions. If you are working on a live system, be absolutely certain you remove the correct failed drive. You can see which drive failed by looking at the contents of /proc/mdstat or consulting Linux kernel message logs. However, a heavily-loaded system will take much more time to complete the repair.īefore installing the new drive, you will need to remove the failed drive.
The commands below may be issued while the system is operating normally.
RAID MONITOR LINUX OFFLINE
Replacing a Failed Hard Driveīecause RAID offers redundancy, it is not necessary to take the storage offline to repair the RAID. Be certain you know which drive has failed before taking further steps. You will see them in the /var/log/messages file or by running dmesg. If your system has experienced a drive failure, Linux kernel error messages will be logged. There’s usually nothing interesting here. List of unused devices (drives or partitions).These indicate that one of the two members is no longer operating. You will see one of the following listed. If a drive has failed, it will be shown on this line. md1: the size of the first array, # of members active/# of members total, and the status of each member.md1: the status of the first array, the type of the array, and each member of the array.Personalities: reports which RAID levels are running (e.g.Simply check the contents of /proc/mdstat: cat /proc/mdstatīreaking down the contents by line, we see: As mentioned above, manually checking the status of a software array is easy. To be certain you are alerted to drive failures, set up automated alerts for hard drive and array failures. Dangerous commands (which could cause data loss) are marked in red. Only minor changes should be needed to perform maintenance on other arrays, but take care. The following examples assume a software RAID1 mirror of two hard drives, which is the most common configuration. By default, Microway installations use partitions 1, 5, 6, 7, 8, 9, 10. These are used to build the corresponding RAID devices md1, md2. You will typically see up to 10 partitions on each drive, such as sda1/sdb1, sda2/sdb. This allows us more flexibility, such as creating a redundant RAID1 mirror for the /home partition while using a faster RAID0 stripe for /tmp. However, Linux software RAIDs may be built using either an entire drive or individual partitions of a hard drive.
RAID MONITOR LINUX FULL
Traditional hardware RAIDs reserve the full capacity of each hard drive in the array. Microway customers are welcome to contact technical support for assistance at any point.
Most commands should be fairly straightforward, but check the mdadm man page for full details. To properly maintain your arrays, you’ll need to learn some basics of the mdadm RAID management utility. You may check the status of all arrays by checking the contents of that file – either with your favorite text editor or a simple cat /proc/mdstat. The only fact you need to know is that the kernel keeps a live printout of array status in the dynamic text file /proc/mdstat. The mdadm utility, which creates and manages the arraysĪs a user, you need not worry much about #1.The Linux kernel, which operates the arrays.Linux software RAID depends on two components:
It is flexible and powerful, but array monitoring and management can be opaque if you’ve not previously worked with a Linux software RAID. Linux provides a robust software RAID implementation which costs nothing and offers great performance for lower array levels (e.g. If you have a larger storage server, a hardware RAID manages the hard drives. In most cases, the RAID is built from two hard drives, but you may also find software RAID on systems with up to six drives. Microway workstations and servers are most commonly outfitted with software RAID to prevent a single drive failure from destroying your operating system installation. There are several advantages to assembling hard drives into a RAID: performance, redundancy and capacity.