Comments on: Data Replication Using rsync

By: Puneet Verma

Puneet Verma — Tue, 28 May 2013 11:53:04 +0000

Does rsync allows master-master configuration ?

By: rct

rct — Wed, 30 Nov -0001 00:00:00 +0000

I don't usually rant about articles, but it seems like this article was overly padded to make a minimum word limit for submission. Many of the options used could have been replaced by using rsync -a.

The paragraph: "rsh=/usr/bin/ssh: This option tells rsync what to use for the remote shell [ ... ] but I used the old school option of rsh=, is really a waste of space and reader's time. As the fine manual page says "a modern rsync uses ssh for its communications". Given that this is Linux magazine, modern == all.

By: grabur

grabur — Wed, 30 Nov -0001 00:00:00 +0000

Rsync is fantastic. Just to add that I always run rsync first with the dry-run option. Just in case!

By: beerse

beerse — Wed, 30 Nov -0001 00:00:00 +0000

With cygwin comes a perfect implementation of rsync (its from the same source). Hence it also works for msDos/msWindows based machines. I even use it on the sd-cards in my camera: just compare it on the local machine between the sd-card (current drive) and the pictures folder. It only copies the new pictures. Much faster with current multi-gb cards.

Be noted however: The fat filesystem only has a 2 second time-stamp resolution. And msWindows timestamps varies around daylight-savingtime changes. Hence use "--modify-window=3602"
And the filename specification differs somehow.

By: bhepple

bhepple — Wed, 30 Nov -0001 00:00:00 +0000

But wait! there’s more!!

rsync _can_ be used to give multi-versioned backup – ie to efficiently backup files with all versions visible at once. This uses the --link-dest option of rsync to make hard links between unchanged files in successive backups – an unchanged file is only stored once. It’s a kind of deduplication at the file level.

This works very well for the typical case of frequent changes to small files. Less well for very large files such as media.

Here’s my backup script that I run daily at minimal cost in time or space: http://bhepple.freeshell.org/oddmuse/wiki.cgi/backup-copy

By: laytonjb

laytonjb — Wed, 30 Nov -0001 00:00:00 +0000

Thanks every one for your feedback on rsync. I really appreciate the feedback that you have given - it helps everyone.

Thanks again!

Jeff

By: uclicktu

uclicktu — Wed, 30 Nov -0001 00:00:00 +0000

Nice article Jeff. For those of us that are cutting our teeth on linux it is very useful for the total explanation of using rsync. Thanks again!