2 Mac mini (early 2009) as a Server (part 2)
How I built in the second hard disk and created a RAID1 mirror
IMPORTANT: This will void your warranty of your Mac mini, it may also cause permanent damage to your hardware and all your data might get lost.
Hard Disk enclosure and cabling
My main goal was to add an additional hard disk and make the system as stable as possible (redundancy).
After I did find a web page describing such a procedure at ifixit.com, I purchased the same cables and started according these guides.
Shortly after I removed the optical drive, I saw the fan which directed the air flow along the optical drive. This was my first show stopper and I changed my mind to continue with the description from the guys at ifixit.com. I already planned to create a plastic part that would direct the heat, but I went for a better idea.
2.1 The laptop DVD drive
I still had an old optical drive from an IBM T30 (but probably any other optical drive from a standard laptop would work also). So, I took it apart and only kept the metal enclosure. There’s enough room inside to fit the 2.5″ disk plus all cables. In addition, the air flow would stay as designed.
So it finally wouldn’t get messy inside the Mac mini and everything was like before, with the exception of a missing optical drive.
Hard Disk Bay in optical drive enclosure
I removed the optical drive. I my case, nothing more had to be done. Once the SuperDrive was stored away, I could simply attach my second hard disk in the “optical drive bay” and screw it to the plastic Mac mini body. You’ll find a picture on the right.
2.2 The question of heat (inside the metal enclosure)
I did some research to optimize the cooling of the drive inside. First, I made several drill-holes in the bottom and backside of the enclosure, so air can flow through. Secondly, I have added a plastic strip at the bottom underneath the hard disk to avoid short circuits and spacer on top of the hard disk, so nothing is covered.
While I was worried about the tight fit, I checked several internal hard disks for Dell Laptops and found out that the so called “Media Bay Hard Disks” are even less cooled than here. Later on I will show some temperature measurements.
2.3 Assembling the Mac mini
It was very easy to assemble the Mac mini again. I did not have the issues the guys at ifixit.com described (getting the cables stored at the right place etc.) because I had my optical drive enclosure. So, just a handful of screws.
2.4 The System Profiler
After the first reboot, the drive was recognized perfectly in the System Profiler. More interesting is how the OS is describing the Bay name. The original drive is in “lower” and the one in the optical drive bay is in “upper” – that is exactly the position.
System Profiler
2.5 Mirroring the hard disks
Now that everything looks very promising, I needed to boot into a different Mac OS X – not the one on the “lower” internal drive I was going to mirror. Usually you can do this by inserting the Mac OS X DVD …
Target Disk Mode
but I did not want to move my USB DVD drive around, so I attached a firewire cable to my Mac mini and Mac Book Pro. My MBP had to be in target disk mode (command + t). I only had to press Alt (Option-key) before booting the mini and choose the target disk inside the MacBook Pro.
Once I booted the Mac mini with my MacBook Pro hard disk, I used the “How to Build a RAID Mirror Without a Re-Format” from the web page www.afp548.com.
AGAIN: This procedure can result in a complete data loss. Please make sure you have at least one good backup.
In my case everything went very well and I could create a complete mirror set over both internal disks in the Mac mini.
2.6 The answer to heat
I’ve done several heat measures, but the most significant is the one after one hour of the drive rebuild. During that time both disks were highly utilized and the temperature shouldn’t go any higher.
Temperature after 1 hr
Both drives are listed in iStat Pro – interestingly enough, the Hitachi drive in the optical drive enclosure is at 48°C (118°F) and the Fujitsu in the normal position at 57°C (135 °F).
I do not see any major issues with this setup, so I’d like to call it “SUCCESS“. The next weeks will show, if a 24/7 operation in summer will keep everything stable.
2.7 Additional Applications I’ve used
2.7.1 iStat – Monitoring the hardware & more
I have already shown some pictures of iStat created by slayer.com. It is donationware and the perfect application to check the various aspects of your Mac. I used the iStat menus application to track down temperature and power consumption on the Mac mini.
2.7.2 RaidEye – Monitoring the RAID
RaidEye is a free application that is used to do two things: First to monitor every software RAID-1 you are running on your Mac and secondly to warn you via email and sound, if the RAID has been degraded.
RaidEye
The preferences are very easy to configure:
RaidEye preferences
3 More information ?
I surely did not give you a step-by-step guide on how to get this accomplished, but the links I’ve provided above show it in depth.
If you want more information, just use the comments section and I try to answer your questions.
Addendum
Hardware:
- Hard Disk: 2.5″, 5400 rpm, SATA
- Cable adapter: slim SATA to SATA
- Cable adapter: SATA power to molex power
- Optical drive: any “old” optical drive (slim notebook form factor)
Tools:
- #0 Phillips screwdriver
- Putty knife 1.5 inch, flexible blade
- Soldering rod and tin-solder
- knife
- borer
Guides & Helper Apps:
- ifixit.com (http://www.ifixit.com/Guide/Repair/Mac-mini-A1283-Terabyte-Drive/660/1)
- afp548.com (http://www.afp548.com/article.php?story=20040827122302975)
- RAID monitoring (http://www.hanynet.com/raideye/index.html)
- Temperature & Power Monitoring (http://www.islayer.com/apps/istatmenus/)