I have a cluster in which lots of user are using. For some users, I have to configure the enviornment (in .bashrc) as A and for some others, I have to configure that as B. Moreover, for some of them, I don't allow them to use a certain software. So how to do this kind of job more efficient? For example, if there is any service such that I can group some user, configure the environment and set their right once?

There are a lot of tools that you may consider using..
* You can perhaps use netgroups (typically with and LDAP solution too). They are very flexible, but I'm not sure if they provide exactly the kind of control you're after
* Use a configuration management tool such as Puppet of CFengine.
* Set up a sudo solution to control access to services. You can use netgroups to fine grain access control
* ACLs


Regards,
kenneho

Thanks for all these suggestions. I am thinking if the following is possible?

In my case, I will modify the path of the installed software and other parameters quite often. So if I did make some modification, I have to modify .bashrc for all users. Is that possible to write a common bashrc and everytime when the user logon, within his/her .bashrc, just include the common bashrc?

For example,

# common bashrc
PATH=$PATH: .....

# user A's bashrc
....
include common bashrc (I don't know if there is any command called 'include' for that purpose)

"man bash" says this:

So when a user log in, the /etc/bash.bashrc (the file name may differ from linux distros) is executed before the user's own bashrc. Is this what you're looking for? Now you only need to host the /bash/bash.bashrc file, which can be done by RPM-files, Puppet/CFengine, custom scripts, or whatever.