Use Midnight Commander (mc) like a pro to move files around

[Alex43]

Not sure where this belongs on the forum so feel free to tow it somewhere else.

 

I have a large number of devices backed up on to an external USB 3.0 WD MyBook and I was having problems accessing them in Windows.  Not sure why but the source directory would keep being reported as "missing" or "disappearing" or something as soon as I started a copy from Windows to the Unraid drive.  Googling around many others reported the same issue with no clear resolution.

 

I decided to plug the drive directly in to the Unraid system and I used the "Unassigned Devices" free plug-in to mount the drive from the UI and then I spawned a shell and I am using Midnight Commander (the command 'mc') to copy the files.  Takes me back to the early DOS days.

 

I had no idea how powerful it was until I tripped across this amazing reference page that I think folks here will appreciate: https://klimer.eu/2015/05/01/use-midnight-commander-like-a-pro/ 

 

One thing that isn't clear to me is what path I should use to copy the contents to the cache drive rather than directly to the disk?  If I copy to the disk array then I get horrible throughput since it needs to do the parity work on each bit at the time.  What is the symbolic path on the cache to use when working at the command line?

Edited November 11, 2022 by Alex43

[JorgeB]

6 minutes ago, Alex43 said:

One thing that isn't clear to me is what path I should use to copy the contents to the cache drive rather than directly to the disk?

/mnt/pool_name, e.g. /mnt/cache

[Alex43]

Not sure where to make suggestions but turning on "safe delete" and "safe overwrite" in the default midnight commander config might be worth considering.  That exposes the option for the various overwrite "yes/no/if different size/if zero size" etc.

[Alex43]

1 hour ago, JorgeB said:

/mnt/pool_name, e.g. /mnt/cache

Odd, I don't have a /mnt/cache just:

 

root@Alex:/mnt# ls
disk1/  disk2/  disks/  remotes/  rootshare/  user/  user0/
root@Alex:/mnt# 

 

Uh oh, when I look in the UI it says the cache isn't mountable.

"Unmountable: Unsupported partition layout "

 

Not sure what happened here, it was working...  Weirdly it is green in the UI but then on the far right says it isn't mountable.  Shouldn't it be red if that is the case?

 

It shows up under the devices in the Tools tab:

0:0:0:0]disk USB Flash Disk 1100 /dev/sda 16.0GB

[1:0:0:0]disk ATA ST4000VN008-2DR1 SC60 /dev/sdb 4.00TB

[2:0:0:0]disk ATA ST4000VN008-2DR1 SC60 /dev/sdc 4.00TB

[5:0:0:0]cd/dvd ATAPI DVD A DH16A1L KH1A /dev/sr0 1.07GB

[6:0:0:0]disk ATA ST4000VN008-2DR1 SC60 /dev/sdd 4.00TB

[9:0:0:0]disk ATA Samsung SSD 840 BB6Q /dev/sde 250GB

[11:0:0:0]disk WD My Book 1230 1050 /dev/sdf 3.00TB

 

/dev/sde is the device.  I can see the kernel barking about errors in dmesg:

 

[158710.373776] sd 9:0:0:0: [sde] tag#4 UNKNOWN(0x2003) Result: hostbyte=0x04 driverbyte=DRIVER_OK cmd_age=0s
[158710.373787] sd 9:0:0:0: [sde] tag#4 CDB: opcode=0x28 28 00 1d 1c 58 80 00 00 08 00
[158710.373791] I/O error, dev sde, sector 488396928 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
[158710.373827] sd 9:0:0:0: [sde] tag#5 UNKNOWN(0x2003) Result: hostbyte=0x04 driverbyte=DRIVER_OK cmd_age=0s
[158710.373832] sd 9:0:0:0: [sde] tag#5 CDB: opcode=0x28 28 00 1d 1c 58 80 00 00 08 00
[158710.373834] I/O error, dev sde, sector 488396928 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
[158710.373839] Buffer I/O error on dev sde1, logical block 61049360, async page read
[158714.769852] program smartctl is using a deprecated SCSI ioctl, please convert it to SG_IO
[158714.769869] program smartctl is using a deprecated SCSI ioctl, please convert it to SG_IO
[158714.769877] program smartctl is using a deprecated SCSI ioctl, please convert it to SG_IO

Edited November 11, 2022 by Alex43

[Alex43]

I shut down the array and rebooted the system and the cache appears to be back (albeit things reorederd as the UBS drive was still plugged in).  Will try a large copy now.

 

Edited November 11, 2022 by Alex43

[Alex43]

Looks like I'm running in to the Samsung + AMD chipset problem with CRC errors that many others have reported.

Running a full Smart diagnostic and also turned off NCQ.  Will report findings.

[Alex43]

I was able to locate a newer firmware for my Samsung drive and after a bit of fiddling finally got the USB to boot and flashed it.  It seems to be stable now (no errors) but use of the drive today suggests the throughput is lower (like 60-65 MB/s for transfers from a machine that also has an SSD) so that requires further testing.