Disconnection from network during large file copy

[dchamb]

I have been running unRAID version 6.0.0 for a few weeks now and I've noticed a phenomenon that occurs typically when I am transferring a group of files that are several gig in size each. The transfer is between a Windows 8.1 64 bit machine using a gigbit ethernet interface. The unRAID machine is also using a gigbit ethernet interface (no wireless between them).

 

The copy will start off fine, and get decent speeds then suddenly it stalls. My file manager software detects the unRAID drive has gone away, but the copy is still frozen. Then suddenly it appears it reconnects and the transfer resumes.

 

I did not have this problem with unRAID 5 so that's what makes me suspect unRAID 6. Has anyone else had this happen?

 

Dale

 

 

[dgaschk]

Use the Plugins page to update to 6.0.1.

[dchamb]

Thanks dgaschk,

 

I performed the update to unRAID version 6.0.1 but the problem still exists. I suspect I might need to take a look at a cache drive. I don't have one configured, so I will look into getting an SSD drive and set it up to be the cache. Maybe write performance with Unraid 6 is not as good as 5 is, but as I understand it writing to a cache drive first would be far more efficient.

 

 

[sureguy]

Do you get any errors in the syslog when this happens?

[thestewman]

Thanks dgaschk,

 

I performed the update to unRAID version 6.0.1 but the problem still exists. I suspect I might need to take a look at a cache drive. I don't have one configured, so I will look into getting an SSD drive and set it up to be the cache. Maybe write performance with Unraid 6 is not as good as 5 is, but as I understand it writing to a cache drive first would be far more efficient.

Have you tried anything other than your normal file manager ?

I was not worried about ultimate transfer speeds bur lack of error so I switched from Windows Explorer which worked OK on 6.0 and now 6.01.

I followed suggestions in the forum and now use Teracopy and successfully recently copied multiple 4tb media files from one drive disc to another as well as from my desktop. The files have a CRC data check after copying them ensuring the data is correct

[dchamb]

sureguy: I checked the logs and nothing shows as an exception

 

thestewman: Today I downloaded teracopy and I am able to get files transferred without exceptions, but that's probably because of the level of persistence in teracopy. I did notice that the Tower device showed as disconnected from the file explorer view (I am using Total Commander).

 

I suspect that since I do not have a cache defined in unRAID, the copies start backing up while unRAID is writing them to the parity and data disks. If my theory is correct, adding a cache drive, particularly an SSD, should eliminate this. However, it would suggest there is a timing out with the copy function which I don't recall this happening in unRAID 5.

 

Dale

 

[thestewman]

sureguy: I checked the logs and nothing shows as an exception

 

thestewman: Today I downloaded teracopy and I am able to get files transferred without exceptions, but that's probably because of the level of persistence in teracopy. I did notice that the Tower device showed as disconnected from the file explorer view (I am using Total Commander).

 

I suspect that since I do not have a cache defined in unRAID, the copies start backing up while unRAID is writing them to the parity and data disks. If my theory is correct, adding a cache drive, particularly an SSD, should eliminate this. However, it would suggest there is a timing out with the copy function which I don't recall this happening in unRAID 5.

 

Dale

Just so you know

I did not use a cache when i recently copied my media and music to new 6tb HGST drives. Each copy was over 3tb and my cache would not be big enough for that as one mass copy. I never observed a disconnect. I have seen other postings about that occurring and was concerned if it happened how would you find the errors.

Terracopy has CRC verify that you can run after the  process has completed.

[dchamb]

Update: I have added a 500GB SSD cache drive and configured my shares to use it. It seems to have helped this problem. I haven't seen a disconnect while doing transfers, and as one would expect the transfers are much faster. If I see anything more of a disconnect I will post it here.

 

When the disconnect did occur, the transfer would pause but not error out immediately. Sometimes it would resume on its own and the file seemed to be fine (I was using the Total Commander copy/move, not Teracopy). Other times the transfer would fail, and restart but stopping for confirmation to remove a duplicate file (the failed transfer would leave an incomplete file). While unRAID was in this disconnected state, Total Commander would show the unRAID shares as disappearing and Plex would show the server was no longer available. So it definitely appears that unRAID is going away from the network and then coming back.

 

Dale