1. Time Capsule Take Apart and Testing
First thing was to procure a Time Capsule (TC) on the cheap, fortunately made possible by eBay. I feel like I got lucky and picked up a 500 GB simultaneous dual-band TC for $91 shipped (Figure 1-1). Once received, I checked that it was working and I got the green light.
Figure 1-1. Simultaneous dual-band TC as received. Green light means it's working.
Next, the TC was configured to bridge the existing network (Figure 1-2) I already had set up with another TC to allow for wireless roaming and to get better coverage. Your requirements for the TC configuration will likely differ, so I will not go into the details of how to set up active roaming, but if you want to know, there's plenty of information on Apple's website.
Figure 1-2. Configuring the TC to extend an existing network.
Once everything was configured and confirmed to be working, the take apart began. There are many other documented examples of this take-apart (e.g. OmniNerd and nakedmac), but it's worth repeating here and I've included some additional details about screw locations, etc. The TC was flipped over and the rubber base of the bottom was peeled back to reveal the metal bottom (Figure 1-3). It was a little difficult to get this started, but working one corner eventually yielded some progress. The rest of the rubber bottom was carefully peeled back in order to keep most of the adhesive on the rubber side.
Figure 1-3. Removing the rubber base on the bottom of the TC.
Once the rubber bottom was completely removed (Figure 1-4) it was set aside in a drawer where it wouldn't get dirty so that the adhesive would remain sticky and no additional material would need to be applied when putting the TC back together. There are ten screws holding the bottom plate in place (Figure 1-4), which were removed using a Philips head #0 screwdriver and set aside in a safe place for later.
Figure 1-4. Locations of the 10 screws holding the metal bottom plate in place.
After the screws were removed, the bottom cover came off easily, but a cooling fan is connected to the plate and plugged into the logic board (Figure 1-5). This was easily disconnected with a pair of tweezers. Note that the fan blows at the HD. Note also the rubber stand-offs for the HD to sit on and the metal posts on the bottom of the HD that line up with the middle rubber stand-offs.
Figure 1-5. TC opened, fan still connected to the logic board. Note the direction the fan blows and the rubber stand-offs to support the HD.
There is a small, rectangular piece of foam on the bottom of the hard drive with a wire running from underneath it to the logic board (Figure 1-5). Lifting up this piece of foam revealed a temperature sensor (Figure 1-6). When the HD gets hot, the TC can then turn up the fan speed to cool it down. Since the HD wasn't going to be used, the temperature sensor and fan were later repurposed to help keep the power supply cool since it seems to be the most common point of failure in Time Capsules.
Figure 1-6. Temperature sensor for the HD.
There are no screws holding the HD in place, so simply unplugging the data and power connections allowed for easy removal of the drive (Figure 1-7). The drive is a 500 GB Western Digital Caviar Blue; hardly a server-grade drive, in my opinion. From here on to the end of this section, there is mostly some testing and trying things out for fun, which are not essential to the goal of the project, but may be interesting nonetheless. If you want to get to the real modification and progress of the project, skip ahead to Part 2: RAID Setup and Testing.
Figure 1-7. HD removed from TC.
Out of curiosity, I powered the TC up again to see what would happen and it still worked (Figure 1-8). That was good news since I would have been pretty upset if I ruined it that quickly.
Figure 1-8. Still works, opened up and sans HD.
Looking at the Airport Utility (Figure 1-9), the TC appeared to operate normally, but there were obviously no disks found.
Figure 1-9. HD removed, therefore no disks found.
The next item of curiosity was the structure of the data on the HD that was in the TC. The little posts on the HD (Figure 1-10) had to be removed before putting the drive into an external enclosure.
Figure 1-10. Posts needed to be removed before use in another enclosure.
Interestingly, there are three partitions that show up in the Disk Utility (Figure 1-11). The "Data" partition (Figure 1-12) is almost the entire size of the drive, which makes sense, and contains only a "ShareRoot" folder (the share was empty when mounted through the TC). There is an "APswap partition" (Figure 1-13) around 2 MB in size, which is empty and I'm unsure what the purpose of this partition is. Likewise, there is another 2 MB partition called "APconfig" (Figure 1-14) that only contains one file called "AFP.reconnect_keys". Opening this file only revealed gibberish, so it is probably some hexadecimal key of some sort. What is interesting is that the configuration of the TC itself is clearly not stored here since it operates as configured with no HD in place (Figure 1-9).
Figure 1-11. Three partitions of the TC HD.
Figure 1-12. Data partition.
Figure 1-13. APswap partition.
Figure 1-14. APconfig partition.
At this point, I wanted to test what happens if any old SATA HD was put into the TC. Recently, I had upgraded a backup HD so I still had a partitioned spare 750 GB drive lying around. After putting the 750 GB drive into the TC and starting it up again, the three partitions I had on that drive all showed up in the Airport Utility (Figure 1-15) and were available shares when browsed to in the Finder (Figure 1-16). However, when any of the shares were mounted (e.g. Figure 1-17), they were empty.
Figure 1-15. Three partitions of a 750 GB HD show up without any special formatting.
Figure 1-16. The partitions are all shared as separate volumes.
Figure 1-17. The volumes all mount as empty shares.
The 750 GB drive was removed from the TC again and connected via an external enclosure. Examining the partitions again showed the creation of a "ShareRoot" folder (Figure 1-18), which is clearly meant to contain any shared contents.
Figure 1-18. Sharing the volume within the TC created a "ShareRoot" folder.
Next, the 750 GB drive was put back into the TC and it was formatted using the Airport Utility (Figures 1-19 and 1-20) to see what happens in terms of partition structure.
Figure 1-19. Erased the 750GB drive through Airport Utility.
Figure 1-20. Drive was erased successfully.
One file was copied to the single accessible share created (Figure 1-21). This was to confirm that the "ShareRoot" folder does indeed contain the shared files. Sure enough, when the 750 GB drive was mounted via an external HD enclosure, the file was in the "ShareRoot" folder (Figure 1-22). Note also the creation of the "APswap" and "APconfig" partitions (Figure 1-23), the contents of which are identical to Figures 1-13 and 1-14.
Figure 1-21. Shared, newly formatted 750 GB HD with one copied file.
Figure 1-22. "ShareRoot" directory contains the copied file.
Figure 1-23. Three partitions created from formatting via Airport Utility.
Getting back to the task at hand and curbing the curiosity experiments, a simple test was run to confirm that an external HD could be connected and made to work via an eSATA cable. There's no reason to think it wouldn't since the pinouts are the same for SATA and eSATA, the only difference being the connector shapes (FYI, eSATA is meant for repeated plugging and unplugging for thousands of uses whereas SATA is only designed for about 50 uses). First, the TC SATA data cable was removed (Figure 1-24), which required some wiggling. Then, a SATA to eSATA cable was pilfered from an eSATA bracket (Figure 1-25).
Figure 1-24. SATA data cable removed.
Figure 1-25. SATA to eSATA connector cables.
Figure 1-26 shows the SATA to eSATA cable plugged into the SATA connector on the TC logic board and an eSATA cable connecting that to an external drive. Once everything was powered up, the TC appeared to operate normally and some data transfer was tested. Figure 1-27 shows a video clip of the data transfer in action.
Figure 1-26. External drive connected via eSATA.
Figure 1-27. Data transfer via eSATA to external drive.
That was proof enough to me that the RAID Capsule idea would work, at least from the TC end. But before I went ahead and hacked apart the TC, I had to get the RAID box set up and do a little further testing.
Continue to Part 2: RAID setup and testing
[Part 1: TC Take Apart and Testing] [Part 2: RAID setup and testing] [Part 3: TC Modding] [Part 4: RAID Modding and Final Assembly]
