"Delayed Write Failed" Error on 2 TB Buffalo DriveStation

[KhunRoger]

Note:

You may want to get a coffee or tea before starting to read this post! It's a rather long story - sorry!

I've been running out of hard disk space and bought a Western Digital 'Green' (WDG) 2 TB drive and a Buffalo 2 TB DriveStation.

The WDG is inside a cheap 'Oker' SATA enclosure.

I started moving my data around in order to get the best use out of the drives I now have.

The first operation was to copy just over 1 TB of files from an old 1.5 TB Buffalo DriveStation to the new 2.0 TB WDG. That worked flawlessly, although it took 49 hours because the rule in force was to compare filesize, timestamps and perform a binary compare. The WDG is to be my backup drive for this data.

I then wanted to copy the same data to my new 2.0 TB Buffalo DriveStation. This drive would then be my main working drive for this data and the original drive would be free for some other use.

But after about 4 hours I got a "Delayed write failed" message and I had to disconnect/reconnect the USB cable for the drive to be recognised.

I am fairly sure, but not 100%, that I was doing the same operation as with the WDG - i.e. copy, with the rules set up to do a binary compare.

I managed to get the drive replaced where I bought it, and I got the same problem with the new one.

So what I did then, was to copy the files again but turn off the binary compare. I also copied just a few folders at a time, not the entire 1 TB.

Having successfully copied the 1 TB of data to the Buffalo, I now wanted to do a binary comparison between it and the WDG, because I knew the WDG data was perfect, but was the Buffalo data the same?

So I started that comparison, but again only processing a few folders at a time. This is where I found something interesting that may be a problem with Beyond Compare.

After finishing a comparison between one folder on the WDG and the same one on the Buffalo, I simply used the "Browse for Folder" icon at the top right of each pane to set up the next comparison.

The left pane was the Buffalo and the right pane was the WDG. Normally it would start the new comparison and all would work as expected. But I discovered that if I waited a long time after a comparison had finished before I started the next one, the Buffalo drive would power down. This appears to be an energy saving mode.

Then, if I started the comparison with the Buffalo in this powered down/spun down state, I would get a "Delayed write failed" message.

After this happened a few times, I decided to "wake up" the Buffalo before starting a new comparison by having a "Windows Explorer" folder open displaying the Buffalo drive and I would click on a folder to open it and get the Buffalo to spin up.

Then I could start the next comparison without any problems!

Phew! There's my story - so what do you think? Could Beyond Compare be doing something too fast or too soon and not allowing a spun down drive a chance to wake up? Or is the Buffalo the problem?

I'm pretty sure it's not my USB hardware as the first copy to the WDG went OK, albeit for 49 hours!

I will also look into disabling this "power down" function as all my other drives stay running and I've not had a problem with them.

Thanks for any help you can give and apologies again for the length of this post!

Roger.

[Aaron]

Hello,

If you perform a Full Refresh (Ctrl+F5) does the Buffalo drive wake-up? Does your device have any methods of configuring this mode or disabling it?

Some NAS devices do not follow all standards, and it could be coded in a way to "look" for Explorer but not BC3 requests. Is it running the most recent firmware/drivers?

[KhunRoger]

Hello,

If you perform a Full Refresh (Ctrl+F5) does the Buffalo drive wake-up? Does your device have any methods of configuring this mode or disabling it?

Some NAS devices do not follow all standards, and it could be coded in a way to "look" for Explorer but not BC3 requests. Is it running the most recent firmware/drivers?

Hi Aaron,

The problem with a full refresh is that it will cause the binary comparison to start again. I guess that's no big deal as I can simply hit the stop button to stop it, and then use the left and right pane "Browse for Folder" buttons to set up the next binary compare on the next pair of folders.

However, it takes a long (but unknown) time for this power down mode to occur, so it's not easy to set up such a test.

But your second question led me to ask on the Buffalo forum how to turn off this power down mode and I got an answer. So I have disabled the power down mode and will let you know if I get the Delayed Write Failed messages again. If I do get it again, I'll do the Ctrl+F5 test.

As for your question about firmware and drivers, it is a new 2 TB DriveStation, so I would expect so, but haven't checked.

If/when then problem occurs again, I'll post more.

Roger.

[KhunRoger]

Although I have disabled the power-down mode (according to the supplied software that reports it has been done), I can still hear the drive spin up if I leave it long enough (about 30 minutes?) without trying to access it.

If I click the "Full Refresh" icon, I can hear the drive spin up and the binary comparison starts again. No "Delayed write failed" message occurs.

Also, if I start the binary comparison of another pair of folders, and I hear the drive spin up, no DWF message appears.

So I am not sure what is happening. According to the software, the power-down mode has been disabled, and yet I can still hear the drive spin up when it is accessed!

But the DWF messages have not occurred the 3 or 4 times I have heard the drive spin up when Beyond Compare starts to access it.

It's a bit of a mystery!

I hope it's fixed. I'll report back if that is not the case.