Can anyone give me exact insight on as to what does compat mode means and is used for in /etc/nsswitch.conf. This is what i know about it
You can put special codes in the /etc/passwd, /etc/group, and /etc/shadow files that cause the system, when you specify the compat method in nsswitch.conf, to combine and modify entries in the local files and the NIS maps. That is, a plus sign (+) at the beginning of a line in one of these files adds NIS information; a minus sign (–) removes information.
Secondly recently i faced an issue where an ssh was being denied for a particular user and user was coming from ldap. When i used getent to reterieve user details it was shwoing the correct but ssh was failing.
The nsswitch.conf entry for passwd was like this
passwd: files vas4 ldap
User was coming from ldap but authentication was failing, then i added an entry like below in /etc/passwd and everything started working
It worked but i was not able to understand how and i am still confused, so anyone please explain about it. It was on RHEL 5.6.
Please do ask for more information if the issue is not clear to you, i would try to explain more.