This topic has been marked solved and closed to new posts due to inactivity. We hope you'll join the conversation by posting to an open topic or starting a new one.
http://www.tomsitpro.com/articles/seagate-8tb-archive-hdd-review,2-822.html wrote: SMR, in its simplest terms, is a method of overlaying data tracks, much like shingles on a roof, to increase data storage density. One of the greatest aspects of SMR technology is its low cost per gigabyte; the Seagate model we have under the microscope retails for 3 cents-per-GB. However, SMR comes with inherent performance constraints, and some implementations have limited compatibility with existing systems
Normal drives shipping today are "PMR" - perpendicular magnetic recording.
With SMR technology, the storage is increased by overlapping the data tracks on the disk. This is cost-effective (which is why these drives are cheaper than PMR 8 TB drives). The downside is that when you write to a track, the next track is trashed because of the overlap. In order to maintain data integrity, the drive has to "ripple" the write until it reaches an unused track (or the end of the drive).
For instance, if you write to track 100, the disk firmware actually needs to do this:
read 101, write 100
read 102, write 101,
read 103, write 102
...
The drive firmware does this in the background automatically with a large cache, but this will greatly slow down write speed if you are doing a lot of sustained writes. And there still been compatibility issues. The linux community has patched drivers, and Netgear made some of their own modifications to the OS 6 firmware.
Where can I find instructions for updating the BIOS and upgrading to 0S6?
Both are in this forum. OS6 isn't supported on the older NAS by Netgear, although they have fixed some bugs that are specific to older NAS anyway. The upgrade is destructive, so you will need to back up your data somewhere.
Re: What is the maximum size for an external USB hard drive for backing up the RNDP6310?
Hi nowthennet,
I believe the highest capacity it can support is 3TB or 4TB. Let's wait for other community members and see if they've tried other higher capacity external USB hard drives.
It came fortmatted as NTFS. I left it as that because I have found that I cannot successfully backup to my smaller 750GB drives if they are formatted to ext3 or fat32. I don't know why that is.
Anyway, my backup currently works fine when I connect my 750GB drives to the front backup USB port. However, when I connect the new 8TB drive, although it shows up on the ReadyNAS Frontview as an 8TB drive it simply does not seem to perform properly. The data that I am backing up from the ReadyNAS is approx 350GB. It manages to back that up no problem on the 750GB USB drives (apart from some complaints about maintaining permissions and some file names and path names that are too long) but when I connect the 8TB drive it takes 24 hours to back up about 30GB of data (approx). It seems to have no prospect of completing the back up.
Is this because the hard drive is too big? What would people expect to happen if the hard drive were too big?
it takes 24 hours to back up about 30GB of data (approx). It seems to have no prospect of completing the back up.
The Pro NTFS write speed is about 17 MB/sec with a traditional PMR USB drive. That should give about 1.4 TB/day overall.
The Backup Plus is an SMR drive, so sustained write speeds will be variable (and slower than the normal PMR drives). But you should still be seeing TB/day not GB/day.
Maybe while you are waiting for mgdm to look at the logs, you might try benchmarking the drive speed on a PC (preferrably using a USB 2.0 port). The drive has a large internal write cache, so you need to test with a lot of data (preferrably ~100 GB).
Re: What is the maximum size for an external USB hard drive for backing up the RNDP6310?
No, the smaller capacity disk works fine (but only if it is NTFS by the way). It is much faster and the backup completes after about 24 hours or so. With the larger 8TB disk the backup fails to complete.
Re: What is the maximum size for an external USB hard drive for backing up the RNDP6310?
If that is the case then updating the BIOS and then upgrading to OS6 (though running that on your unit is not supported) may make sense. OS6 does have some fixes to work better with drives that use SMR.
http://www.tomsitpro.com/articles/seagate-8tb-archive-hdd-review,2-822.html wrote: SMR, in its simplest terms, is a method of overlaying data tracks, much like shingles on a roof, to increase data storage density. One of the greatest aspects of SMR technology is its low cost per gigabyte; the Seagate model we have under the microscope retails for 3 cents-per-GB. However, SMR comes with inherent performance constraints, and some implementations have limited compatibility with existing systems
Normal drives shipping today are "PMR" - perpendicular magnetic recording.
With SMR technology, the storage is increased by overlapping the data tracks on the disk. This is cost-effective (which is why these drives are cheaper than PMR 8 TB drives). The downside is that when you write to a track, the next track is trashed because of the overlap. In order to maintain data integrity, the drive has to "ripple" the write until it reaches an unused track (or the end of the drive).
For instance, if you write to track 100, the disk firmware actually needs to do this:
read 101, write 100
read 102, write 101,
read 103, write 102
...
The drive firmware does this in the background automatically with a large cache, but this will greatly slow down write speed if you are doing a lot of sustained writes. And there still been compatibility issues. The linux community has patched drivers, and Netgear made some of their own modifications to the OS 6 firmware.
Where can I find instructions for updating the BIOS and upgrading to 0S6?
Both are in this forum. OS6 isn't supported on the older NAS by Netgear, although they have fixed some bugs that are specific to older NAS anyway. The upgrade is destructive, so you will need to back up your data somewhere.
If it is going to make it more likely to work then I am prepared to go down to a 2TB drive, although 4TB would make it a lot more comfortable in terms of storage.
How were you able to tell that it is an SMR drive?
PMR internal drives retail about $300 US and up at the moment (WD80EZRX and ST8000DM003); your backup-plus was quite a bit less (and quite close to Seagate internal SMR drives). Another possibility was that it had 2x4TB internally (which is what the WD my book duo does). Either way, it made me wonder so I googled it, and found this review: http://www.techradar.com/us/reviews/pc-mac/pc-components/storage/disk-drives-hdd-ssd/seagate-backup-...
It's a bit tricky to avoid SMR with seagate backup drives, because their datasheets are pretty sketchy. If you drop down to a 4 TB 3.5" drive you should be safe, since their smallest 3.5" internal SMR model is 5 TB. They do have a 4 TB 2.5" SMR though, so avoid the 4 TB backup plus portable. So maybe two of these: https://www.amazon.co.uk/Seagate-Backup-Desktop-External-Drive/dp/B00HSYI58U/ Total price is about the same as the 8 TB backup plus.
I'd avoid the cheaper Mybook 8 TB duos - they use 2 drives inside, and I don't think they will be as reliable.
Another option would be to get a USB 3.0 enclosure, and use that with an internal drive. Then you know what you are getting (since the internal drives always have pretty complete datasheets). That is usually more expensive though.
Re: What is the maximum size for an external USB hard drive for backing up the RNDP6310?
Sounds like you have a good path forward then.
BTW, SMR isn't a bad choice for backup drives, especially incremental backups. It is quite cost-effective. But your NAS pre-dates SMR, and doesn't have the driver patches needed to use them reliably.
