ReadyNas Duo & Proprietary File System

[wonmoi]

I was almost deadset about buying a ReadyNas Duo when I found out that it uses a 'proprietary' filesystem that would not be able to be read by any x86-based hardware.
Does this means that if I run RAID 1 on my ReadyNas & it crashes, I am unable to take one of the disk out & mount it on to my computer & recover the data?

[yoh-dah]

It's not really a proprietary filesystem but rather a filesystem based on 16K blocksize. Sparc, IA-64, and any of the sparc instruction set ReadyNAS (Duo, NV/NV+, 1100) will be able to mount the filesystem fine.

[wonmoi]

Thanks for the reply yoh-dah.
I am a NAS newbie & am not aware of this 16KB blocksize & SPARC stuff.
I just want to be able to recover/read my data if my NAS hardware fails instead of one of the disks.
So if I were to buy the ReadyNas Duo & run it on RAID 1 and the NAS hardware fails sometime later how can I recover my data without having to buy another ReadyNas?

[yoh-dah]

Thanks for the reply yoh-dah.
I am a NAS newbie & am not aware of this 16KB blocksize & SPARC stuff.
I just want to be able to recover/read my data if my NAS hardware fails instead of one of the disks.
So if I were to buy the ReadyNas Duo & run it on RAID 1 and the NAS hardware fails sometime later how can I recover my data without having to buy another ReadyNas?

The format is compatible with all the sparc-based ReadyNAS (which are all the ReadyNAS we've shipped other than the Pro which just started shipping last month). You can purchase a replacement, get a RMA if the Duo fails within 3 years (5 years for NV+, Pro), or purchase a used one (check Ebay). That's probably your cheapest alternative -- even if you could recover with a Linux server, it'll probably cost you more than purchasing another Duo. Or you can opt to have the recovery done by Netgear Support even out of warranty for a very reasonable fee. Keep in mind even if you do work with Linux, that doesn't mean you'll be able to recover data.

If you're still uncomfortable with these solutions, you can opt for the Pro (more costly however), which will give you full compatibility with all Linux distros out there today.

[Mechanix]

If you're still uncomfortable with these solutions, you can opt for the Pro (more costly however), which will give you full compatibility with all Linux distros out there today.

Or you follow this usefull tip:

viewtopic.php?f=10&t=21003&hilit=16k

[wonmoi]

Thanks all for your help.

[CenterJarod]

This discussion was startling to me, as I'd recovered data from an NV+ in the past, and I've now realised it must have running 3.x firmware. So thanks to wonmoi for raising this, as we sell Duo units to home theatre users.

I'm sorry to be a party-pooper, but the obvious question has to be asked: what can possibly have been so important about implementing a 16kb blocksize over the 4kb blocksize (without even an *option* to use 4kb) that it could have outweighed the benefit of data recovery on a non-ReadyNAS device in the event of hardware failure?

The only thing I can think of is a greater volume size to account for larger hard drives, but then that reason can't work for two reasons: 16kb was implemented without even an option for people to choose 4kb, and the same format/firmware is used on 2-drive Duos as it is on 4-drive NV+ units, so someone would know that they were deliberately crippling Duo users (i.e. home users who by definition are without access to lots of funds *or* replacement hardware) in an attempt to help a small proportion of NV+ users.

Can someone please explain why this happened? And is there a reason why we can't even have an option to choose a 4kb block size during volume format that would return the benefit of reading data in the event of hardware failure? (I view this as basic insurance; sure it might be unlikely to happen, but that's why we have drive mirrors, UPSs, and burglar alarms...)

Thanks you,
CJ

[beisser]

the reason is simple. performance. with 4 kb block sizes you would see a lot less performance from the nases.

[Mechanix]

the reason is simple. performance. with 4 kb block sizes you would see a lot less performance from the nases.

Hmm interesting, with iometer i get the same results before and after i changed the blocksize

read: 9.65 MB/s
write: 10.29MB/s

100Mbit/Fdx

[CenterJarod]

the reason is simple. performance. with 4 kb block sizes you would see a lot less performance from the nases.

Hmm interesting, with iometer i get the same results before and after i changed the blocksize

Thanks, Mechanix - you beat me to it! I was about to ask beisser if he/she had any metrics to give a sense of the scale of the speed increase we would be 'missing' if we went to 4kb block size.

If we take Mechanix's stats as being accurate, are there any other supposed benefits to 16kb block size?

[Grievous]

You're probably not going to see more than mechanix's number on a 100mbit connection like he posted. Because while the theoretical max is 12MB/s, there's a lot of overhead involved. If you want to see a performance difference, you would need to do it on a gigabit connection.

[CenterJarod]

Thanks, Grievous - that's a good point. Can anyone help with these figures?

My assumption is that, before entering into a no-retreat situation like this moving to a 16kb block scenario, some serious testing and consideration was done in the lab to ensure this was a worthwhile exchange (speed over data recovery in a worst-case). So perhaps a technician could post some of the test results, so we can all see the difference, and know if this is a reason for the move to 16kb block size? Even just an indication of the order of magnitude, if the actual test numbers are not for release.

For a home theatre environment, as our clients are using the Duo for, the performance with the 4kb block size is fine so I'm now looking for a way to revert to a 4kb block size. If we go back to a v3 firmware and reformat and then upgrade firmware, will this work? If so, where can we safely get a v3 firmware from?

Many thanks,
CJ

[Mechanix]

For a home theatre environment, as our clients are using the Duo for, the performance with the 4kb block size is fine so I'm now looking for a way to revert to a 4kb block size. If we go back to a v3 firmware and reformat and then upgrade firmware, will this work? If so, where can we safely get a v3 firmware from?

Many thanks,
CJ

Hey CJ, take a look at this thread.
Zappes explained in detail how to convert to 4k blocks.

[CenterJarod]

Thanks again, Mechanix. Alas, I don't do Linux, so I'm left with the other way: install v3 firmware, reformat, upgrade to v4 firmware. This is why I'm after a v3 firmware. Can anyone point me in the right direction?

[Mechanix]

Thanks again, Mechanix. Alas, I don't do Linux, so I'm left with the other way

Your ReadyNAS IS Linux. So you only have to install the SSH addon. Much easier then down- upgrade the firmware.