Multiple entry in .ssh/config file

Here is a link to one post on ssh config file.

However, if you want entries for lot of servers with their IPs or names, then it could be cumbersome to add all the entries in the .ssh/config file. So, here is a shortcut notation:

Host 1 2 3 4 5 6
Hostname 192.168.1.%h
    User 
    
    Ciphers arcfour

where '%h' denotes the IP that you use in the ssh command.

The following escape character substitutions will be performed:
             ‘%d’ (local user's home directory), ‘%h’ (remote host name), ‘%l’ (local host name),
              ‘%n’ (host name as provided on the command line), ‘%p’ (remote port),
              ‘%r’ (remote user name) or ‘%u’ (local user name).

nice little bash function to search for running processes

Here is a nice little handy function that I use very regurlarly.

You can use this function with parameter to just grep for that or just type psa to see all the running processes.

Just put this in your .bashrc file.

You might find it useful:

psa () 
{ 
    if [[ $1 == "" ]]; then
        ps -eaf;
    else
        ps -eaf | grep --color=auto -i $1;
    fi
}

nall – schedule your tasks like a pro

nall is a utility to run your scripts ( for whatever ) every defined period. Here is description:

Description : Nall is a small gtk+ application that discretely fits into your freedesktop

system tray (such as trayer).

Its purpose is to spawn periodically every kind of script and display a

one-line output in the tooltip window. The main usage of nall is monitoring or

just notifying of almost everything (it just depends upon your imagination and

ability to script).

For installation :

bash – refer the first parameter from last command quickly

To refer to first parameter from the last command quickly, you can use

!^

Note: This can also be referred as “!!:1“

bash refer parameters from the current command

In bash you can use

!#

to refer to any parameter from the current command, example:

mv ak amit.!#:1.txt
ls amit.ak.txt

Download Ticket Service – dl is now on fedora.

From : http://www.thregr.org/~wavexx/software/dl/

“dl” is a file exchange service that allows you to upload any file to a web server and generate a unique ticket for others to download. The ticket is automatically expired according to the specified rules, so that you don’t need to keep track or cleanup afterward. “dl” also allows you to grant an anonymous, one-time upload for others to send you a file, without the requirement of account management.

Continue reading

Debuggging bash cron scripts.

I have to several times debug scripts that I get complain about working when logging in normally but they do not work when run in cron mode. So, quite a lot of times, redirecting the stderr of the script is all that is required to see what is happening, but sometimes that just does not help if the script is calling another script which is mis-behaving and under lot of other conditions. So, how to at-least take a look at why these are failing, login with ssh.