[lug] Interface CRC error on USB connected SATA drive

[Lee Woodworth]

On 09/10/2016 11:02 AM, Jed S. Baer wrote:
> On Fri, 9 Sep 2016 20:40:58 -0600
> Davide Del Vento wrote:
> 
>> Try something like
>> tar --mtime='2010-01-01' cf - | md5sum
>> from both locations to rule out file corruption (remove mtime if you
>> want to include mtime int the checksum). Try first on a subdir to
>> check if this is correct as is (I haven't tested it).
>> You might want to do this in smaller chunks.
> 
> I like this idea. It's interesting how it played out.
> I used tar cf - --mtime='2010-01-01' . | md5sum in both source and
> destination, using a subdir having only 6 files. Sums did not match.
> Manually checked all files using diff, and they are identical.
> 
> All files in the directory match the file glob h*, but
> tar cf - --mtime='2010-01-01' h* | md5sum produces a different checksum
> from using . for the input files list.

It would be interesting to see if tvf produces the same file names
and file name order for both cases. If the file order for the cvf
commands differ the hashes would differ but a recursive diff would
not.

> 
> Using the h* file glob for input to tar, the sums match in both source
> and destination. Also using your suggestion of smaller chunks, this
> should work fine, just using file globs a*, b* ... quickie shell script.
> 
>> My best practices:
>> - always use tmux, and (in reality "or" suffice) set the scroll back
>> options in your shell to infinite
> 
> I use screen sometimes, though I've heard tmux is better. In practice,
> I've never before needed huge scrollback.
> 
>> - never put long-running jobs in background, always use a new tmux tab
>> (or terminal tab) for doing other stuff
>> - if I anticipate there might be problem, redirect stderr to stdout
>> and pipe into a file with tee (easier to grep and parse than tmux or
>> terminal scrollback) -- if it weren't so complicated I would also keep
>> a copy of the stdout and stderr separately, besides the merged one
> 
> Good advice, and I probably would've done something smart like that if I
> hadn't been distracted thinking of other things. I do have a defense in
> place against spammy programs, but I sometimes forget to use it. I have a
> little script named deadlaunch.
> 
>   #!/bin/bash
>   # launch a gui, with annoying output sent to /dev/null
>   exec nohup $* 1>/dev/null 2>&1 &
> 
> So, e.g. 'deadlaunch bluefish'
> 
> Yeah, it could be improved upon, and adding an ad-hoc logfile would be a
> good enhancement.
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