I had three HR20s (owned) that I upgraded the internal drives to WD 2TB Green drives. In May, I picked up an HR44-500, a SansDigital TR4UTBPN 4-bay hardware RAID 5 eSATA enclosure, and four WD Red 2TB WD20EFRX drives. Before upgrading the internal drives on the HR20s I had used single-drive eSATA enclosures on them, so am very familiar with the process. I set up the HR44 and the TR4UTBPN eSATA and four drives, and fired it up. I didn't give it a second thought until this week when I noticed some recording were marked for possible deletion and there was less than 10% free space. What, 6TB filled already? Since there's no way to check in System Info whether you are using eSATA or not, I could only assume I was recording on the internal drive. Shutting the HR44 and eSATA down, I removed the eSATA and restarted the HR44. Sure enough, there was the playlist I was using, so it was never recording on the eSATA. I tried several times to restart the HR44 with the eSATA attached, but no joy. Suspecting a bad cable, I ordered another. Did not help. Since the new TV season starts this month, and I record entire seasons of some shows before watching, it was urgent to get this working. I've already removed two of the HR20s and the third will go soon. My TiVo Premier XL is being replaced Friday with a new TiVo Roamio Pro six-tuner with 3GB. This was I can record shows on both DirecTV and Comcast. I also record OTA on the HR20 for some can't miss shows, so all bases are covered: satellite, cable, and OTA. When I pull the HR20 I'll add an AM21 to the HR44.
I finally got the HR44 to see the eSATA RAID. I disconnected the RAID box from the HR44, hooking it up to the HR20, restarting, and letting the HR20 process it. I then reversed it. When I started the HR44, it's now seeing the TR4UTBPN and its four 2TB Western Digital Red drives in RAID5. 6TB of space. I hope this helps others who may have a problem with eSATA.