[SATLUG] RAID5 Recovery - ddrescue: copy completed!

Samuel Leon satlug at net153.net
Sun Aug 23 13:00:36 CDT 2009

David Labens wrote:
> ddrescue has completed, here's the command and resulting screen info:
> -------------------------------------------
> root at RCH-SERVER:/# ddrescue --no-split /dev/sdb /dev/sda resclog1
> Press Ctrl-C to interrupt
> Initial status (read from logfile)
> rescued:         0 B,  errsize:       0 B,  errors:       0
> Current status
> rescued:   250057 MB,  errsize:   1835 kB,  current rate:   48103 kB/s
>    ipos:   250059 MB,   errors:      49,    average rate:   34888 kB/s
>    opos:   250059 MB
> Not sure what to do next!  
> Should I remove the bad drive & reconnect the other 3 (including the old one) and try to reassemble the array???  Or, should I try to redo it without the old one connected?
> David Labens
> San Antonio, TX

To my knowledge "--no-split" means not to rescue anything.  But 
according to the log it would appear that 1825kb was rescued.  For good 
luck I would run the command again with error recovery turned on:

ddrescue --direct --max-retries=3 /dev/sdb /dev/sda logfile

And as you noticed the drive number assignments don't always follow the 
plug number.  Once all the drives are plugged back in it should go back 
to the way that it was.  Just check and make sure.

So went you first ran ddrescue, it copied the 80gb os drive onto the new 
250gb new drive?  ddrescue keeps a log file of where it starts and stops 
reading at (I am guessing that would be resclog1?).  So if you copied 
80gb of the os drive onto the new drive and then fixed the drive 
numbers, then that 250gb drive would have the first 80gb of it still 
from the os drive.  If you formatted the newdrive and then reran that 
command without first deleting (or renaming) resclog1, then it would 
started where it last left off. Meaning the first 80gb of the newdrive 
would have nothing on it? Did you ever delete the logfile?

If not I would recommend running it again just to be sure:

ddrescue --no-split /dev/oldDrive /dev/newDrive resclog2
and then:
ddrescue --direct --max-retries=3 /dev/oldDrive /dev/newDrive resclog2

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