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OS6 on a legacy device in 2018.
Hello there NAS-owners. Starting this thread instead of me going off topic in the thread about ’restriping’. I just switched from OS4 to OS6 and so far i am happy with the change. The new OS is ...
Guise?
Not much activity anymore in this thread, unfortionately.
Anyways, i have more questions:
* As i mentioned, the system temps were right below 100c, could my NAS have taken some damage or would i know by now if it has? The system runs flawlessy as it is now.
* The new firmware has been released: 6.9.5, is it safe to upgrade? The NAS nags about it all the time.
* Somewhere in the process of me backing up stuff something must have gone wrong, i have found several files being corrupted and that is not good. A file can’t be corrupted just like that right?
* Are there any particular settings i should enable or disable in the NAS to prevent corruption? I want my data to be as safe as possible and i’m running RAID-6 (to be extra sure).
* If i would want to, would it be possible to go from RAID-6 to RAID-5 without having to factory default again?
* Oh, is there any way to fix the corrupted files? It is mostly videofiles that has been affected, haven’t found any musicfiles corrupted yet. I have checked my backups too and there is the same corruption there so as i mentioned, somewhere in the process something went wrong.
* What is disc ROT protection? Should this be enabled?
Would be happy if someone shared their expertise, i really like the professionalism i see on this forum.
Not much activity anymore in this thread, unfortionately.
Anyways, i have more questions:
* As i mentioned, the system temps were right below 100c, could my NAS have taken some damage or would i know by now if it has? The system runs flawlessy as it is now.
* The new firmware has been released: 6.9.5, is it safe to upgrade? The NAS nags about it all the time.
* Somewhere in the process of me backing up stuff something must have gone wrong, i have found several files being corrupted and that is not good. A file can’t be corrupted just like that right?
* Are there any particular settings i should enable or disable in the NAS to prevent corruption? I want my data to be as safe as possible and i’m running RAID-6 (to be extra sure).
* If i would want to, would it be possible to go from RAID-6 to RAID-5 without having to factory default again?
* Oh, is there any way to fix the corrupted files? It is mostly videofiles that has been affected, haven’t found any musicfiles corrupted yet. I have checked my backups too and there is the same corruption there so as i mentioned, somewhere in the process something went wrong.
* What is disc ROT protection? Should this be enabled?
Would be happy if someone shared their expertise, i really like the professionalism i see on this forum.
- doubt any damage has occurred, I am sure if there was you would have already had problems
- sure seems to be fine I don't see anyone making complaints about it in the forums.
- many things can cause corruption, network errors, application errors, software/hardware errors, user errors, virus and malware issues. no raid or device is a replacement for backups. backups = multiple copies of your data on different devices and ideally in different locations (think about floods or fire or theft etc).
- raid 6 and enabling the checksums/bitrot protections is a good start. backups are the only complete solution.
- no you cannot go from raid 6 to raid 5. You don't necessarily have to factory default, but you would need to delete the data volume and recreate a new raid 5 volume, so the result is the same... you would have to completely backup then restore all data.
- depends on the file and the corruption, but if the corruption is in your backups then it sounds like it may have already been there for some time so its difficult to know when or where it occured. If these are just media files, you can simply re-rip bluray/dvd/music. Time consuming yes, but if the validity of your data is in down, its best to start with a clean slate anyway. If they are business or personal files, well probably be unlikely to fully recover unless you have even older backups from before they were corrupted.
- bitrot protection utilizes checksums on parts of the file system, so that if for some reason a drive started failing by randomly changing a zero to a one or vice versa, the checksum should detect the file corruption and either repair from parity (when it is able) or notify the user so that an uncorrupted backup can be restored. Note this protection is only at the filesystem level, it would not know or detect if a file is corrupted by an application or network or user error.
the use of checksums does have a minor impact on performance (cpu has to calculate the checksums on the fly and they have to be written/read from the disk), but in general it should be enabled for most use cases.
- Thanks for your reply.
The time when i suspect the corruption took place is when one drive was being replaced in the NAS and during that time it gave me some time to backup, the NAS did this several times and i just had to reboot and it did it again. Something like that.
I remember something about when it finished or almost finished (not sure which) it displayed something about that the volume was vulnerable or something like that.
Maybe i was lucky that i could do backups of the system at all.
It took forever to backup and from time to time the copying process would cancel and show some message about the files not being available anymore and i had to restart the computer i was copying to (Win10 x64) and then it worked again.
That’s the problem, basically: the only backups i had was the files on the NAS, yes i know, not a very good backup plan.
Alright, then i will keep this configuration, turn on bitrot protection and upgrade to the latest firmware.
I guess the only last thing i can do to be completely safe is to do a memory test (sometimes during the process i replaced the 2gb RAM to 4gb). But it should be alright i guess since there are no strange errors or anything like that and i can’t recall me needing to restart the NAS even once.
Are there any ways to check a file for corruption? I think for example WinRAR can do that, but maybe that’s a different story.
Are there any ways to verify a directory and save the results in a file so that one can do a quick check if needed? I’m not that educated in this regard but i know of some solution generating .md5 files, i just don’t know enough to put it in practise (best program and stuff like that).
TeknoJnky wrote:
- no you cannot go from raid 6 to raid 5. You don't necessarily have to factory default, but you would need to delete the data volume and recreate a new raid 5 volume, so the result is the same... you would have to completely backup then restore all data.
Actually if you have an empty slot in the NAS, you can switch to raid-6 without data loss. This would also require that the three largest disks currently in the NAS be the same size.
PerfectOnline wrote:
Are there any ways to verify a directory and save the results in a file so that one can do a quick check if needed? I’m not that educated in this regard but i know of some solution generating .md5 files, i just don’t know enough to put it in practise (best program and stuff like that).Some years ago I started doing this for selected folders (before I owned a NAS). I still use QuickSFV (though it is old, it still works), creating an "sfv" file in each folder.
You can also use something like QuickPar (also old) or MultiPar for this. (I've used QuickPar, but not MultiPar). These create signature files similar to QuickSFV, but also can create repair files from limited amounts of file corruption. For instance, if the repair files are 10% of the folder size, they can recover from up to 10% of corrupted data blocks in the files. This operates similarly to RAID redundancy btw, but is more sophisticated.
As you say, you can also zip (or rar) the folders - compressed archives also have built-in integrity checks. WinRar does include "recovery records" which are similar to the par2 repair files created by QuickPar. Of course you can't access the data as easily if you do that.
These approaches aren't automated (and if they were, you'd risk updating the signatures when the files became corrupted). So they do take some discipline to use. I don't think it'd be practical to use them on frequently updated folders.
FWIW, btrfs checksums will also detect corrupted files. But it's not easy to access those corrupted files - making repair (or partial recovery) difficult. The bitrot protection is an interesting ReadyNAS feature (which uses the checksums and the RAID partity blocks), but I haven't seen posts here from people saying that it recovered their files. I do have it enabled, but my main strategy for protection from data loss is backups (using snapshots to protect against accidental deletion or modification).
- Thanks alot for the reply guise!
I will take a look into this whole thing about .sfv and the likes, it sounds interesting and i do want a feature which i can use if i ever suspect something to be wrong with a file, let’s say a .flac file that sounds strange, it would be sweet to at least know that the file is OK and rule that out, in this example leaving it to a bad rip.
I have enabled bit-rot-protection.
Oh, and a funny thing: since the NAS was worthless to control a single 120mm fan (almost cooked my system) i installed a little thingy that i bought, a voltage regulator so now it is connected to a MOLEX and a single yellow cable goes to the MBU giving me the possibility to see the actual RPM’s, but nothing more than that, the controller is attached on the outside of the NAS so i can control the flow exactly as i want it. 1700rpm’s seems fine, i do think that a system temp if around 50c is too much but i have bought heatsinks and this should not be an issue if my calculations are correct.
Regarding the thing about RAID6-5, i have no empty slots. Would it be possible to remove one disk, shrink the volume and then later add the last disk again or is this too much trouble?
I did the update for the firmware so i am currently running 6.9.5 and current bad things to report are: 0.
Everything seems fine. You cannot shrink a volume on a ReadyNAS. So if all slots are full, you have to backup, wipe the volume, create a new RAID6 volume, and restore data.
- I see, i am running RAID6 now but after thinking some more about it i’ll keep my current configuration.
I still think it’s strange that i have corrupted data but it must have ocurred when the NAS was busy restoring a drive and me copying stuff from the NAS in the meantime.
If it happened some other time than that it leaves me to doubt the safety of the NAS. I want my data to be uncorrupted.
I remember there being a function under OS4 where you could see if there were any errors during the traffic on the connection but there doesn’t seem to be a function like that anymore when running OS6. I think it were called packages or something like that.
PerfectOnline wrote:
I remember there being a function under OS4 where you could see if there were any errors during the traffic on the connection but there doesn’t seem to be a function like that anymore when running OS6. I think it were called packages or something like that.I still have 4.2.31 running on my pro-6, and I don't know of any such package.
You can download the log zip file and look in network_settings.log.
- On my little Duo it is in: Home/Network/Interfaces/Show errors
I’m almost certain that the same function was present on the RNDU6000 in OS4 but i could be wrong though.
Does network errors always equal corrupted files? - Mr StephenB,
i followed your advice and took a look at the par-thing and downloaded MultiPar and it is a lovely program, i use it now for all verified folders.
Are there any settings i should be extra careful with? I want a single file that can verify a whole directory and i have figured that out.
I put the redundancy to 0% since i just want to be able to verify, the NAS should’nt fail me but just in case.
Perhaps some redundancy should be selected? If so, how much?
This shouldn’t be necessary since the NAS itself should be safe with RAID6 and so on.
PerfectOnline wrote:
On my little Duo it is in: Home/Network/Interfaces/Show errorsOk. Just download the log zip file and look in network_settings.log That will show you the same stats.
PerfectOnline wrote:
Does network errors always equal corrupted files?No. SMB uses TCP/IP (as do most file sharing protocols). Network errors will result in re-transmissions of the data, so usually the files aren't corrupted. If the connection times out due to the errors, then a file might not be completely sent, and in that case it would be corrupted.
Still, if you are are seeing a lot of network errors you should figure out the cause and fix it.
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