Comments on: Backup or archive your Equallogic with lessfs.

By: Jeff

Jeff — Wed, 16 Feb 2011 02:59:58 +0000

Since I was super bored today, I wrote a python tool called ddsum (http://ddsum.com) that is like dd5sum but lets you change the hash algorithm. It let’s you calculate the hash of something before and after compression for example:

dd if=/dev/sda | ddsum -H sha512 | bzip -9 | ddsum -H sha512 – sda.img 2>sda.img.sha512

By: maru

maru — Mon, 07 Feb 2011 10:12:30 +0000

dd5sum is a tool that reads data from a source and writes it to a destination while calculating a md5 checksum.
You can download the source from: http://www.lessfs.com/wordpress/wp-content/software/dd5sum.tar.gz

By: Ivan Ivanov

Ivan Ivanov — Sun, 06 Feb 2011 23:34:09 +0000

I played around a bit and got this to work by using tee as in:
md5=$(dd if=/dev/sda bs=1M count=1 | tee/pooldata/$VOL/$DATE/$lv | md5sum – 2>&1)

By: Ivan Ivanov

Ivan Ivanov — Sun, 06 Feb 2011 23:05:32 +0000

In the following line:
md5=$(dd if=/dev/sda bs=1M | dd5sum – /pooldata/$VOL/$DATE/$lv 2>&1)
isn’t the “dd5sum” supposed to be “md5sum”? Also wordpress does weird things with the dash.
And another thing… looking at the md5sum man (if this dd5sum is actually md5sum) I fail to see how md5sum would calculate the hash of the data coming on the pipe from dd, and then write this same data to /pooldata/$VOL/$DATE/$lv. In this case md5sum simply calculates the md5 hash of the stream data and also the /pooldata/$VOL/$DATE/$lv file (if it exists). Am I missing something?

By: How to setup EqualLogic Replication « Michael Ellerbeck

How to setup EqualLogic Replication « Michael Ellerbeck — Tue, 22 Dec 2009 18:03:27 +0000

[…] is an interesting post on using lessfs http://www.lessfs.com/wordpress/?page_id=172 for more efficient backup. Possibly related posts: (automatically generated)DFS Replication – […]