passwd: authentication information cannot be recovered : How to resolve ?

While trying to change user password on linux server i got the below error.

error : passwd: Authentication information cannot be recovered

# passwd mades

Changing password for user mades.

passwd: Authentication information cannot be recovered

root:

I tried to change as my user login also but got the below error

mades> passwd mades

 passwd: Authentication token manipulation error

mades>

Then i found that in /etc/pam.d/system-auth there is a entry missing. I added the below entry then its got resolved.

"password    sufficient   /lib/security/$ISA/pam_unix.so remember=6

This above entry we need to add in /etc/pam.d/system-auth file. Normally the below 4 lines should be there in system-auth file.

=================================

password    sufficient    pam_unix.so md5 shadow nullok try_first_pass use_authtok remember=6

password    requisite     /lib/security/$ISA/pam_cracklib.so retry=3 minlen=10 dcredit=-1 try_first_pass

password    sufficient   /lib/security/$ISA/pam_unix.so remember=6

password    required      pam_deny.so