Index
Subject
: [lug] Digest (6 messages)
From
: lug-owner@lists.ncsu.[redacted]
Date
: Sun, 20 Aug 2017 16:42:14 -0400
The Lug Digest
Volume 1 : Issue 408 : "text" Format
Messages in this Issue:
201708/1 : Overwriting old/corrupted files in a backup
Jeffery Mewtamer <mewtamer@gmail.[redacted]>
201708/2 : Re: Overwriting old/corrupted files in a backup
Quentin Young <qlyoung@ncsu.[redacted]>
201708/4 : Re: Overwriting old/corrupted files in a backup
Brian Pike <bapike@gmail.[redacted]>
201708/3 : Fall Semester LUG meetings
Quentin Young <qlyoung@ncsu.[redacted]>
201708/5 : Meeting time
Quentin Young <qlyoung@ncsu.[redacted]>
201708/6 : Planning Meeting Monday, 08/21 7:00 P.M.
Quentin Young <qlyoung@ncsu.[redacted]>
----------------------------------------------------------------------
Date: Mon, 14 Aug 2017 18:44:48 +0000
From: Jeffery Mewtamer <mewtamer@gmail.[redacted]>
To: IAVIT Tech Talk List <talk@lists.iavit.[redacted]>,
Linux for blind general discussion <blinux-list@redhat.[redacted]>,
lug <lug@lists.ncsu.[redacted]>, raspberry-vi@freelists.[redacted]
Subject: Overwriting old/corrupted files in a backup
Message-ID: <CAO2sX334LzHonfU8msM8TPrLo98awKQ0HcsAyBXAzh7=RPLPTg@mail.gmail.[redacted]>
Okay, so using the cp command with the -Rn switch is convenient for
say copying my Music folder from my home directory to an external hard
drive or the SD card for my portable Media player when the destination
already has an older copy without needing to copy everything already
present in the old copy, manually determining what's been added and
copying manually, or dealing with a bunch of prompts. It also allows
an aborted copy to more or less be resumed from where it left off.
This method is simple enough to not require scripting or complex
command syntax, but it does have a few downsides:
1. It won't overwrite corrupted files left by an interrupted copy, and
such files are too rare for manual searching.
2. Files that have been altered don't get copied. unless they've
changed filename. Not a big issue for copying my Music folder since
those files are seldom altered, but copying say, my writing folder can
lead to the backup media containing only older drafts of some
documents.
3. It tells me nothing of files from an older copy that have been
deletd/renamed since the last copy. jdupes can find old files on the
destination media if the new file is just a rename, but it can't help
with files that have been altered as well as renamed.
I suppose what I'm looking for is a command line utility or script
that executes the following pseudo code:
Given directories source and destination:
for every file found in both source and destination:
if file.source != file.destination
prompt user whether to overwrite one version of the file with the
other or to add the files to a list for later examination.
For every file only in source:
search for match in destination.
If match found prompt user towhich to rename to match.
If not match found, copy to destination.
For every file only in destination:
search for match in source.
If match is found, prompt user to which file should be renamed.
If no match is found, prompt user whether to copy of delete.
If anyone knows of command line utilities to help with this task, it
would be greatly appreciated.
------------------------------
Date: Mon, 14 Aug 2017 20:32:38 -0400
From: Quentin Young <qlyoung@ncsu.[redacted]>
To: lug@lists.ncsu.[redacted]
Subject: Re: Overwriting old/corrupted files in a backup
Message-ID: <03b95c2b-64da-beb6-c7cd-87269946dcfb@ncsu.[redacted]>
rsync will do mostly what you want. I don't believe it has an option to
confirm
overwriting for each file, but there are some switches to control when
and how
it overwrites a destination file with the source copy. As for dealing files
that have been modified and then renamed, at that point you're really
dealing
with a different file. There are ways to get a metric on similarity, such as
hamming distance, but if any copy or sync utilities support that I would be
surprised.
Generall rsync tries to minimize the amount of copying involved as best
it can
out of the box, but there are options that will make it update a file
based on
modification date, for instance.
On 08/14/2017 02:44 PM, Jeffery Mewtamer wrote:
> Okay, so using the cp command with the -Rn switch is convenient for
> say copying my Music folder from my home directory to an external hard
> drive or the SD card for my portable Media player when the destination
> already has an older copy without needing to copy everything already
> present in the old copy, manually determining what's been added and
> copying manually, or dealing with a bunch of prompts. It also allows
> an aborted copy to more or less be resumed from where it left off.
>
> This method is simple enough to not require scripting or complex
> command syntax, but it does have a few downsides:
> 1. It won't overwrite corrupted files left by an interrupted copy, and
> such files are too rare for manual searching.
> 2. Files that have been altered don't get copied. unless they've
> changed filename. Not a big issue for copying my Music folder since
> those files are seldom altered, but copying say, my writing folder can
> lead to the backup media containing only older drafts of some
> documents.
> 3. It tells me nothing of files from an older copy that have been
> deletd/renamed since the last copy. jdupes can find old files on the
> destination media if the new file is just a rename, but it can't help
> with files that have been altered as well as renamed.
>
> I suppose what I'm looking for is a command line utility or script
> that executes the following pseudo code:
> Given directories source and destination:
> for every file found in both source and destination:
> if file.source != file.destination
> prompt user whether to overwrite one version of the file with the
> other or to add the files to a list for later examination.
> For every file only in source:
> search for match in destination.
> If match found prompt user towhich to rename to match.
> If not match found, copy to destination.
> For every file only in destination:
> search for match in source.
> If match is found, prompt user to which file should be renamed.
> If no match is found, prompt user whether to copy of delete.
>
> If anyone knows of command line utilities to help with this task, it
> would be greatly appreciated.
--
Quentin Young
President, LUG @ NC State
------------------------------
Date: Mon, 14 Aug 2017 21:13:40 -0400
From: Brian Pike <bapike@gmail.[redacted]>
To: lug@lists.ncsu.[redacted]
Subject: Re: Overwriting old/corrupted files in a backup
Message-ID: <CAFpBnz0VEGV6avzXEvTDeahx2PxGM1WTYfQF8MCXieDXvdFHRQ@mail.gmail.[redacted]>
I'm a fan of rdiff-backup, which is similar to rsync but designed to handle
incremental backups. In particular, the most recent backup is always a
collection of normal files. Like rsync, I'm sure, you can have it check if
a file has changed based on filename, date/time stamps, size, hash, or the
actual contents. It probably doesn't handle renamed files very well.
Another option that might work is to put all your files of interest in a
version control system like subversion or git. I've used subversion to keep
track of a large, 1-person project that I worked on using multiple
computers, though everything was plain text.
Thanks,
Brian Pike
On Aug 14, 2017 8:32 PM, "Quentin Young" <qlyoung@ncsu.[redacted]> wrote:
rsync will do mostly what you want. I don't believe it has an option to
confirm
overwriting for each file, but there are some switches to control when and
how
it overwrites a destination file with the source copy. As for dealing files
that have been modified and then renamed, at that point you're really
dealing
with a different file. There are ways to get a metric on similarity, such as
hamming distance, but if any copy or sync utilities support that I would be
surprised.
Generall rsync tries to minimize the amount of copying involved as best it
can
out of the box, but there are options that will make it update a file based
on
modification date, for instance.
On 08/14/2017 02:44 PM, Jeffery Mewtamer wrote:
> Okay, so using the cp command with the -Rn switch is convenient for
> say copying my Music folder from my home directory to an external hard
> drive or the SD card for my portable Media player when the destination
> already has an older copy without needing to copy everything already
> present in the old copy, manually determining what's been added and
> copying manually, or dealing with a bunch of prompts. It also allows
> an aborted copy to more or less be resumed from where it left off.
>
> This method is simple enough to not require scripting or complex
> command syntax, but it does have a few downsides:
> 1. It won't overwrite corrupted files left by an interrupted copy, and
> such files are too rare for manual searching.
> 2. Files that have been altered don't get copied. unless they've
> changed filename. Not a big issue for copying my Music folder since
> those files are seldom altered, but copying say, my writing folder can
> lead to the backup media containing only older drafts of some
> documents.
> 3. It tells me nothing of files from an older copy that have been
> deletd/renamed since the last copy. jdupes can find old files on the
> destination media if the new file is just a rename, but it can't help
> with files that have been altered as well as renamed.
>
> I suppose what I'm looking for is a command line utility or script
> that executes the following pseudo code:
> Given directories source and destination:
> for every file found in both source and destination:
> if file.source != file.destination
> prompt user whether to overwrite one version of the file with the
> other or to add the files to a list for later examination.
> For every file only in source:
> search for match in destination.
> If match found prompt user towhich to rename to match.
> If not match found, copy to destination.
> For every file only in destination:
> search for match in source.
> If match is found, prompt user to which file should be renamed.
> If no match is found, prompt user whether to copy of delete.
>
> If anyone knows of command line utilities to help with this task, it
> would be greatly appreciated.
>
--
Quentin Young
President, LUG @ NC State
[Attachment of type text/html removed.]
------------------------------
Date: Mon, 14 Aug 2017 20:46:10 -0400
From: Quentin Young <qlyoung@ncsu.[redacted]>
To: lug@lists.ncsu.[redacted]
Subject: Fall Semester LUG meetings
Message-ID: <24dc2be1-1543-5cd7-084e-96d0b5409ad9@ncsu.[redacted]>
Hi LUG & affiliates,
Fall semester starts this week so it's time to spin up the club once
more. This week we will have no meeting. Next week we will have our
semester-start planning meeting where we will agree upon an optimal
meeting time, arrange elections, discuss topics of interest, potential
events and firm up our strategy towards world domination. I'm
tentatively putting that at the traditional 7:00 P.M. Tuesday evening
(08/22), EB2 3001. However, if you want to join us and can't make that
time slot, please respond to this email (either to the list or to me)
and, being a small club, we'll make an effort to adjust to accommodate
everyone.
Also, if anyone happens to have a 21-inch to 19-inch rack adapter for a
1U server, for sale or for gift, unicast me. <3
Best,
--
Quentin Young
President, LUG @ NC State
------------------------------
Date: Sun, 20 Aug 2017 01:50:39 -0400
From: Quentin Young <qlyoung@ncsu.[redacted]>
To: lug@lists.ncsu.[redacted]
Subject: Meeting time
Message-ID: <8eb25942-f434-b6e4-bd7f-05ea98368646@ncsu.[redacted]>
Hi folks,
I had a couple people let me know that Tuesday nights at 7 don't work
for them this semester. Is anyone opposed to moving our meeting date to
Monday at 7?
--
Quentin Young
President, LUG @ NC State
------------------------------
Date: Sun, 20 Aug 2017 16:42:09 -0400
From: Quentin Young <qlyoung@ncsu.[redacted]>
To: lug@lists.ncsu.[redacted]
Subject: Planning Meeting Monday, 08/21 7:00 P.M.
Message-ID: <eb5baf16-4c39-2139-5732-fc8541287bea@ncsu.[redacted]>
Hi LUG,
The semester planning meeting will take place tomorrow at 7 P.M. in EB2
Room 3001. As a reminder we will be discussing LUG activities for this
semester, call for speakers, meeting times, elections, etc. It has been
moved to Monday to accommodate the schedules of some of our members.
Be there or be an equilateral rectangle U25A0.gif
<https://en.wikipedia.org/wiki/File:U25A0.gif>
--
Quentin Young
President, LUG @ NC State
[Attachment of type text/html removed.]
------------------------------
End of [lug] Digest (6 messages)
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