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Two hard drives failure in two months, finally I think I should have a file server with raid 5 to protect my data. this server is mainly keeping all my pics, personal video, backup documents and movies, also its download machine and SSH server. so here is what I planning to do.

fist of all, here is my hardware list, most of parts are from my old computer:

  • CPU: AMD 4850e
  • Motherboard: Gigabyte GA-MA78GM-S2H with 5 x SATA II 3GB/s connectors
  • Memory: 4 GB DDR2 (I need suggestion here, how many ram I need for this kind of server, I mean without swap only ram, I have 10GB ddr2 ram, I can put more if it needs it)
  • HDD: planning to buy 3 x 3TB WD red hdd(use them to build raid 5), also I have 2 x 2TB WD green hdd
  • SATA II pci card: 4 x SATA II connectors

I will install ubuntu on raid 5 drive, but I have not much knowledge of here is my quesitons.

  1. when hdd failure, ubuntu still functional? can I login and access my data?
  2. will ubuntu show me which hdd failure?
  3. if I replace the failure hdd, is the recovery process automatic?

Since I have other two 2TB old hdd, I am thinking how to use them after all. is it possible ubuntu to create 2 raid system? raid 5 use new 3TB hdd, and raid 1 use my two old 2TB hdd. can Ubuntu handle it? if not, since my motherboard support raid 1, maybe I can do this by my motherboard?

also in the future, if I need more space, can I buy more 3TB hdd to put on? How ubuntu handle that?

thank you so much for your opinions.


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I can only answer a couple questions as myself am curious about if ubuntu will warn me. Here is what I know so far, if the RAID is degraded, ubuntu will tell you on the next startup and will ask you if you want to continue. Ubuntu will keep running if one of the drives fail, but in a DEGREADED state, this is very bad and you should shut off all services you don't need writng/reading to the disks because if another drive fails, your data is essentially gone.

Also for the RAM situation, 4GB should be good, but install htop [sudo apt-get install htop] and every so often check to see if the RAM is at it's max and if it is, just add more in. The more the better :)

Sorry I could not help you with the automatic process of recovering the RAID or if ubuntu shows you if it is degraded while in operation.

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Ubuntu (the Linux kernel) can handle both RAID-1 or RAID-5.

  1. Either of them can tolerate the failure of one disk.
  2. It will also tell you which drive is no longer in function.
  3. Yes the recovery process is automatic: all you have to do is to add a new disk to your degraded (i.e., faulty) RAID array.

You can even grow your RAID-5 array that is add new disks to it to increase its capcaity (it might be a bit complicated and time-consuming but possible anyway).

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