On Fri, Sep 07, 2018 at 01:15:59PM -0400, William Oliver wrote:
I've been reading the thread about backing up hard drives with
interest. I have a similar question.
I have a 4 TB external USB hard drive that I've been doing backups on.
Unfortunately, it's starting to get a little flaky -- not being
recognized by my laptop, etc. The problem got better when I changed
enclosures, but now I'm a little paranoid that it might continue to
degrade. So... I'd like to copy the data to a new USB external hard
drive.
The drive is about 96% full.
I have tried plugging the old drive into a USB port, plugging the new
drive into a USB port and simply doing a cp -Ruav from one to the
other. It goes gangbusters for awhile, but after about 5 or 10 gigs,
it slows down to almost nothing. At the end of 8 hours of copying,
it's plugging along, but I only have about 400 gigs copied.
I've searched the intertubes, and it seems that this is a problem
people have asked about across multiple distros. It is apparently
associated with some sort of cacheing issue in the kernel.
Is there some solution to this? I tried rsync, but it was even slower.
I haven't tried dd, which was mentioned in the other thread; I might
give it a shot this weekend. But if there's a known fix for this, I'd
love to hear it.
is this computer a laptop, or a desktop? If a desktop, you could
probably pull the drive from its enclosure, open the desktop and
attach the drive (using an appropriate cable) to a SATA port in the
desktop. then boot up, make sure it doesn't mount the "new" drive,
then do your copies that way. Should be faster, and it removes all
the USB baggage from the equation.
Good luck!
Fred
--
---- Fred Smith -- fredex(a)fcshome.stoneham.ma.us -----------------------------
Show me your ways, O LORD, teach me your paths;
Guide me in your truth and teach me,
for you are God my Savior,
And my hope is in you all day long.
-------------------------- Psalm 25:4-5 (NIV) --------------------------------