Louwrentius

This system is no longer operational and has been decomissioned (2017)

This is my NAS storage server based on Debian Linux. It uses software RAID and 20 one terrabyte hard drives. It provides a total usable storage capacity of 18 terrabytes in a single RAID 6 array.

One of the remarkable side effects of using 20 drives within a single array is the read performance of over one gigabyte per second.

I made a small script that converts the output of cat /proc/mdstat to an actual date and time telling you when the RAID rebuild / reshape is finished.

This is the link to the correct version of the script.

Example:

debian:~# ./raid-rebuild-eta.sh

Estimated time of finishing rebuild / reshape:
Mon Jun 29 00:45:07 CEST 2009

When formatting a RAID device with an EXT filesystem, it is always advised to specify a stride size. The format utility will take this stride size into account when formatting a device. The stride size is the number you get when you divide the 'chunck' size, as specified with MDADM by the filesystem block size (almost always 4K).

So a 128 KB chunck size gives you a stride of 32. A nice and simple utility to calculate your stride can be found here:

http://busybox.net/~aldot/mkfs_stride.html

Please note that the stripe-with option does not seem to work on Debian Etch. Maybe because that option is too old or too new.

I also think that most recent tools automatically detect and calculate the correct stride size for you.