How can I set environment variables when I ssh login to my Unix box by passing custom arguments?

Question

I want to pass some parameters as part of my ssh connection that I can use to set custom variables for my login to do certain things or run certain scripts. How do you do this running Putty on Windows machine, connecting via SSH to a CentOS machine?

Answer 1

On the CentOS machine, create a file in your home directory named .bashrc and set your environmental variables in there. For example, the contents of the file can be:

export VARIABLE=foo

Here's some discussion of this: http://tldp.org/LDP/Bash-Beginners-Guide/html/sect_03_01.html

[edit]

Thanks for the clarification.

You can use the SendEnv and AcceptEnv options. This will allow environmental variables on the client to be passed to the server.

You will also need to change the server's sshd_config file to specify which environmental variables are accepted by the server. I'm not sure what you'll need to do with PuTTY to issue the SendEnv option, but that should get you started.

Answer 2

You could can modify PermitUserEnvironment in sshd.conf to allow processing of ~/.ssh/environment or "environment=" options on keys in ~/.ssh/authorized_keys.

The format of these two files differs. ~/.ssh/environment is lines of VARIABLBE=VALUE where in ~/.ssh/authorized_keys the environment option is environment="VARAIBLE=VALUE"