[BozemanLUG] more RAID questions

[Scott Dowdle]

Greetings,

Just to let everyone know, Rob popped into the #ubuntu-montana IRC channel on Freenode... where many of us Montana Linux folks hang out... and we discussed the various partitioning options for quite a while.  I think we got it figured out.

Basically I came up with an example scheme that goes something like this:

sda
[  1 | 2 |       3                         ]

sdb
[  1 | 2 |       3                         ]

sdc
[  1 | 2 |       3                         ]

sdd
[  1 | 2 |       3                         ]

All drives are partitioned exactly alike and partitions 1 and 2 are relatively small with the bulk of the space being in the 3rd partitions.

The partition type is fd Linux raid auto.

>From that raw material 3 RAID device can be created:

md0 - RAID 1 made from sda1 and sdb1 with sdc1 and sdd1 being spares or unused

md1 - RAID 1 made from sda2 and sdb2 with sdc2 and sdd2 being spares or unused

md2 - RAID 5 made from sda3, sdb3, sdc3 with sdd3 being either a spare or part of the RAID depending on which is more important... having more storage space or having a spare.

md0 could be mounted either as /boot or /.
md1 could be used for swap space.
md2 could be either / or /whatever - the spot where the file server would share files from

That would make for a RAID 1 bootable system with spares and a fair amount of storage for the file server... offering around 1.9TB - 2.9TB depending of if a spare in the RAID 5 was wanted.

Anyone have any other suggestions?

In the IRC chat we noted how hardware RAID is always drive based whereas Linux software RAID is more partition-based which offers quite a bit of flexibility.


TYL,
-- 
Scott Dowdle
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Belgrade, MT 59714
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