Shell
Printing a sequence of letters or numbers
Shell Tips
January 14, 2008 | COMMENTS

Some times, while scripting in your favorite shell (I mean Bash !! 😃 you need to print a sequence of letters or numbers. Don’t write it yourself ! Script it using seq or curly braces !

nicolas@macvin:~$ seq 1 10
1 2 3 4 5 6 7 8 9 10
nicolas@macvin:~$ seq 0 2 10
0 2 4 6 8 10
nicolas@macvin:~$ echo {1..10}
1 2 3 4 5 6 7 8 9 10
1
2
3
4
5
6
nicolas@macvin:~$ echo {a..g}
a b c d e f g
1
2

Hope this will help you while doing a loop or building some hash directories :

nicolas@macvin:~$ mkdir -p test/{1..10}/{1..10}

Enjoy !

How to flush DNS Cache in Mac OS X ?
Shell Tips
January 3, 2008 | COMMENTS

Joy ! I just get my new [Mac Book Pro][1] (2Go RAM / 2,4Ghz Core 2 Duo / 160Go HDD / etc.). So I’m playing a lot with [VMware Fusion][2] and multiple host (debian, ubuntu, solaris, windows, etc.) with a great fluidity ! A big improvement for me who was working with an old DELL Laptop with 1Ghz Celeron and 512Mo of Ram...

But, while playing with my new laptop and my multiple virtual instances I needed to flush my DNS Cache. So, here come the tips :

With Mac OS X <= 10.4 :

macvin:~ root# lookupd -flushcache

With Mac OS X > 10.5 :

macvin:~ root# dscacheutil -flushcache

Cheap SAN and secure backup solution for small-sized platform
Shell Case Study
November 26, 2007 | COMMENTS

Here is a quick post about a cheap SAN and secure backup architecture solution for small-sized platform (5/10 servers). In this study case we will see how to use Network Block Devices (nbd) and soft-raid with mdadm. I design it for my personal web platform which is a small one. Last day, I was missing of free space on my backup server and I was angry by the idea to rent a most expensive server to store my backup while I had lot of unused space on my other servers.

1. Initial platform
2. New platform
3. How to do it ?

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Working with Bash Aliases (Alias/Unalias)
Shell Tips
August 25, 2007 | COMMENTS

Aliases allow a string to be substituted for a word when it is used as the first word of a simple command. The shell maintains a list of aliases that may be set and unset with the alias and unalias builtin commands.

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Bash Help Sheet
Shell Tips
April 15, 2007 | COMMENTS

Forgot a command or a shortcut in your favorite shell ? Here is a small help sheet with most used commands !

I read it some times for remember me some useful shortcuts that can help you to work faster with bash shell. I does this help sheet sometimes ago and never take time to finish it correctly. May be I’ll do a better version when I’ll have more time 😃
Bash help sheet thema : wildcards, escape keys bounds, tabs keys bounds, controls keys bounds, alt keys bounds...

bash help sheet ** Download it **: