24 November 2010


As an early Christmas gift, I was suckered into buying two 2TB hard drives the instant I heard they were $90 apiece on Newegg (it so happens that 2TB drives are $70 apiece for Black Friday sales). They were destined to go into the first of my four Dells that I got from the Stata Loading Dock a while back for my media and archive server. My plan was to install ArchLinux on the drives, but with a twist: I wanted to install a software RAID 1; that is, to have the drives be perfectly mirrored at any instant in time. Sure, such a setup is overkill for one person, especially without any critical data, but setting one up would be good experience.

Obviously the first step in setting up any storage array is to install the hardware. Since these Dells do not have a second SATA port, I had to either (a) use an adapter to convert SATA to IDE or (b) get a second SATA port. Step A was easier at the time I got the drives because I had already picked up two SATA->IDE adapters from a Reuse posting. Strangely the adapters did not work in the Dells, but worked perfectly fine on my quadbox. Luckily, a week later Bayley found a 4-port SATA PCI card and generously gave it to me. I installed it in the Dell, plugged in both drives, and fired up the machine. It worked! Surprisingly, the Dell reports the drives as IDE drives. Strange.

Now it is time to install Arch. Having not a clue as to where to start, I Googled some guides. The first article that I got was an install guide on Arch's wiki and it was rather long and was not trying to do what I wanted to accomplish. However, it was a start, and I felt confident enough to work my way through it.

On my first attempt, I followed all the instructions, only forgetting to add the "mdadm" and "lvm2" hooks before the "filesystem" hook in mkinitcpio.conf. I think everything else in the setup process went fine. Then I rebooted the machine, which seemed to be fine until the OS decided to fall back to the ramfs. Uh oh. This was my first time working in a castrated (and borked) Linux; I was shocked when "halt" and "reboot" did not work. I hit ctrl-d to logout, which proceeded to induce a kernel panic. Derp.

Evidently the install failed somewhere. On my later takes, I tried manipulating the commands, and sooner or later I began to understand what each of them did. I also learned (more or less the hard way) that formatting a 2TB disk takes approximately five minutes. Google proved helpful in collecting further resources; some other webpages that I read included a Ubuntu mdadm RAID1 thread, Arch RAID0 thread, and mdadm stop/delete array thread. Unfortunately, none of them ended up helping me set up a working RAID1 array. Double derp.

After two weeks of on-and-off work and trivial progress, I got rather frustrated, stressed, and upset. My self-imposed deadline of Thanksgiving crept faster and faster, which put more pressure on me to get this stupid thing working. I decided to try one last time on the eve of Thanksgiving, hoping that something would work out. It didn't. Grub decided to be annoying, and when I got Arch to partially load after copying the Grub files onto the boot partition, Arch decided to fall back to the ramfs and proceeded to kernel panic. Blah. I finally relented and installed Arch on one disk and set up the other disk as a vault for incremental backups, which took less than half an hour. *mega sigh of relief*

Although this most definitely is not a RAID1 array, it is still a decent alternative for redundant storage. As for learning how to set up software RAIDs in Linux, I'll probably do that on another machine during IAP (another name for January, in which we have no classes), when I'm not Battlecoding, cramming for Linear Algebra or Differential Equations, or churning out PSETs for Intro to C++.

tl;dr Setting up (uncommon) configurations on Linux + deadline in the near future = major stress. I totally do not want to do IT-related work as a career.

UPDATE: So somehow Bayley sort of talked me into installing Ubuntu Server on the box because Ubuntu Server has a nice RAID configuration utility. Plus, Ubuntu Server is not as bloated as the regular Ubuntu. I suppose with 2TB of disk space I should not be fussing about an extra 150MB or so. Hmmm....

No comments:

Post a Comment