RAID 0 Capabilities
Is it possible to add disks to the existing RAID0?
In practice, no. The only option is to back up the array data, recreate the array (add disks), and then restore data from the backup.
Is it possible to take the disks out from a RAID 0 on the fly?
No, because the very concept of RAID 0
supports neither hot spare nor hot swap.
When you pull out a disk, the whole array fails.
Is it possible to use different disks in RAID0?
Disks from the different vendors If the disks have the same characteristics (capacity, type, and RPM),
then they can be used in a RAID 0 simultaneously.
Disks with different capacities It is not advisable to use such disks because array capacity is calculated based on
the smallest disk, thus leaving a part of the disk space on the larger disks unusable.
Disks that differ by type, e.g. SSD and rotational hard drive or rotational hard drives with different RPM.
It is not recommended to combine such disks into an array because array performance will be limited by the slowest
disk in terms of read/write speed.
Disks with different ages. It doesn't matter what are the ages of the disks you use for RAID 0.
If you have disks with data which are not in RAID, is it possible to create RAID0 on these disks
in one operation and keep all the data intact?
No. To create a RAID0 on these disks and keep all the data intact first you need to back up all the data, create a
RAID0 on these disks and only then restore data to the array from the backup.
Is it possible to transfer RAID 0 member disks from one device (e.g. NAS, a RAID controller)
to another similar device and expect that the array will work?
Generally, no. In any particular case you can address this question to your device vendor.
If you still want to transfer RAID0 yourself, keep in mind that configuration of
RAID0 is described by the following parameters: block size, disk order, and start offset.
If during transferring the array to another device you manage to keep the parameters, then most likely everything will be OK.
Here goes a couple of tips for the arrays configured using default settings.
- If you have exactly the same device you need just to transfer the disks correctly.
- If you have the similar device, make sure that the devices have the same default settings.
Secondly, you need to know how disk order on the original device correlates with disk order on the device on which you are
going to transfer the array. Once you have checked all the above, transfer the disks.
If there is a RAID controller with multiple ports, is it possible to use several ports for a RAID 0
and the remaining ports for another array, possibly of a different level?
Typically, yes. Most if not all controllers support multiple arrays per controller,
as long as requirements for a minimum number of disks are satisfied.
Is it possible to transform a RAID0 to some other array layout and keep all the data intact?
If you have a software RAID0 (Windows or mdadm in Linux), no.
If you have a hardware RAID controller, refer to the controller manual.
|