I'm thinking that the smart thing to do with my raid setup is to replace the drives before they start failing and as they start to get old... I can't really afford a lot of cloud backup space, and I want to get a jump on the guaranteed eventual fail of my drives due to wear.
I have 3 2TB drives with GPT, grub, a small system raid1 partition, and a large raid5 home partition. I'm using Arch Linux.
I was going to replace the drives one at a time. I wanted to post my plan of action and see if anyone could think of a reason why it wouldn't work or if there was a better way to do it.
figure out which device (ie
/dev/sda) I am replacing by unplugging it physically and checking
/proc/mdstat to find out the
/dev/sdx that fails.
Plug it back in and use sfdisk to copy the partition table
sfdisk -d /dev/sdx > partition.layout
Put in a new physical drive of the same size
sfdisk /dev/sdx < partition.layout
mdadm to add the new drive to the array based on the instructions on the arch wiki.
mdadm --add /dev/md0 /dev/sdx1 mdadm --add /dev/md1 /dev/sdx2
Reinstall grub? wait for the resync to complete, then repeat the whole process with the other 2 drives?
I guess my question is mostly like, will this work out? is there anything I'm missing? I don't want to miss something obvious and lose all my data.
Thank you very much for any assistance/insight.
Just to get the results of the discussion down in the same place, I wanted to say that I figured out how to have mdadm and smartmontools (smartd) montior and notify me via email if things start going bad with my hard drives. I set up ssmtp with a gmail account that I have synced to my phone.
Since I already bought the new drives, I'm going to keep them around, and swap them in as things go bad. It is my understanding that eventually all hard drives fail. Thanks for the suggestions and protips on how to do that (without degrading the array). Once I can afford an upgrade I'm going to use ZFS with an ECC motherboard/memory/etc. and thanks for the tips in that direction. Thanks a lot you guys really helped :D