Topic: RAID1: second HDD slight smaller than first

[Jáder]

I've been using RAID1 with just one disk for one year.
Now I bought a new 1TB HDD, from same supplier (Seagate) and even same size (1TB)... but it was not enough.
The new one (in fact are 2 of them, later I'll move to RAID5 following - http://wiki.contribs.org/Raid#Convert_Software_RAID1_to_RAID5) are a few megabytes smaller than previous one.

There are something I could to do, like use mdadm to shrink / partition on 1st disk a few MB to be able to do RAID1... or even directly to go to RAID5 using Wiki info from above link?

Thanks

Jáder

[Stefano]

no.. in this case you can only backup, reinstall and restore..

[Jáder]

What will happens (bad things only ...hehehe) if I create a new RAID5 array with 2 new 1TB HDDs and copy data from old RAID1 (single disk again) to new RAID5 array.

I'm sure I can loose anything if my old 1TB disk fails... but it's not new to me (using RAID1 w/single disk nowadays!)

[Stefano]

What will happens (bad things only ...hehehe) if I create a new RAID5 array with 2 new 1TB HDDs and copy data from old RAID1 (single disk again) to new RAID5 array.

Jader, backup your data, setup the server with the new disks, restore your backup

any other way could be very dangerous.

[purvis]

Another user mentioned that SME can have two sets of Raid 1.
Any thoughts on that people?

[Jáder]

Yes, that would be another option, create another RAID1 with my 2x 1TB HDD (a few MB smaller) and copy data from original RAID1 to this one.

After test (reboot, reboot) I could remove 1st 1TB HDD and add it to RAID, migrating from RAID1 to RAID5!
FYI: I have 190TB of my own data and 320TB of Affa backup (for my clients!)

[idp_qbn]

Just a thought about RAID5 - I once read (3 or 4 years ago) that RAID5 on 3 disks is very "busy" - it keeps the disks very active, rattling away. My own experience when I tried a 3-disk RAID5 array was just that - the HDD light seemed to be on constantly. (That's an impressive sample of 1, so it may not be reliable).

I now have 4-disk RAID5 and the situation is normal - occasional flickers of the HDD light.

Cheers
Ian

[Boris]

Yes, that would be another option, create another RAID1 with my 2x 1TB HDD (a few MB smaller) and copy data from original RAID1 to this one.

After test (reboot, reboot) I could remove 1st 1TB HDD and add it to RAID, migrating from RAID1 to RAID5!
FYI: I have 190TB of my own data and 320TB of Affa backup (for my clients!)

190TB and 320TB, Terabytes? Really? Not GB (Gigabytes)? Not trying to be a smart a$$. Just seeing that you are operating with 1TB drives, so amounts of data in GB sounds more realistic and can be backed up and moved in hours (reasonable time)

[Jáder]

hehehe... that's the problem these days... TB x GB...
ofcourse it was GB... hehehehe...sorry my typo! :$