01.15.06
RAID controllers reliability
Something that I am currently wondering about is whether people use cheap RAID controllers in Mission-critical environments.
According to my tests with a VIA VT6421 RAID 0/1 controller, there is nothing less reliable than RAID 1…. However, drawing such a conclusion seems inadequate, especially since RAID is so popular.
Using 2 Maxtor 250 GiB Hard Drives, configured as a RAID 1 (mirroring) array using VIA VT6421’s BIOS, and the Ubuntu GNU/Linux Operating System with a 2.6.12-10-686 kernel, RAID is a disaster. In fact, on the 2 installations I did with this setup, both failed at some point :
- With the following partitions : /boot (100 MiB, ext3), / (20 GiB, ext3), swap (1 GiB), /home (the rest, ext3) , after an installation of Ubuntu server and a reboot, the / partition is mountable, but trying to read any file in / leads to a “Cannot access blocks beyond filesystem limits”
- With the same partitions, except that / was of type reiserfs, installation is fine, mount is fine, except that trying to copy more than 5 GiB of data crashes the system.
Of course, everything runs fine without RAID, so I am wondering what the real problem is :
- The VIA VT6421 RAID controller in RAID/1 mode ?
- Any cheap RAID controller in RAID/1 mode ?
- The Linux driver for these FakeRAID controllers ?
If anyone has an answer to these questions, do not hesitate to post a comment or send me an email.