Linux / Unix: Sed Substitute Multiple Patterns [ Find & Replace ]

Posted on in Categories last updated January 20, 2012

I‘m using the date +’%D_%T’ to store Unix system date and time in a shell variable called $_now:

_now=”$(date +’%D_%T’)”
echo $_now

Outputs:
01/20/12_16:10:42

I’d like to replace / and : with _. I’m aware of the following sed command:

sed ‘s/\//_/g
> s/:/_/g’ <<<"$_now"

Outputs:
01_20_12_16_14_09

How do I specify two pattern within the same sed command to replace | and : with _ so that I can get output as 01_20_12_16_10_42?

Rsnapshot WARNING: Could not lchown() symlink "/path/to/file" Error and Solution

Posted on in Categories , , , , , , , , , , last updated November 3, 2009

I got rsnapshot based backup server up and running for my network under Debian Linux 5.x. But, whenever I run a backup job using the following command:

rsnapshot -v -c /root/rsnapshot.server1.conf hourly
I get the following messages on screen:

WARNING: Could not lchown() symlink “/nas/.rsnapshot/hourly.1/server1.example.com/etc/alternatives/locate”
WARNING: Could not lchown() symlink “/nas/.rsnapshot/hourly.1/server1.example.com/etc/alternatives/nc.1.gz”
WARNING: Could not lchown() symlink “/nas/.rsnapshot/hourly.1/server1.example.com/etc/alternatives/jexec-binfmt”
WARNING: Could not lchown() symlink “/nas/.rsnapshot/hourly.1/server1.example.com/etc/alternatives/servertool”

How do I fix this problem?