I followed the guide from the below link to set up a ldap server. After everything is finished, I configured a client for ldap authentication and I can search the entries in ldap using the command ldapsearch -x ZZ but when I am trying to login to the client using a ldap user, the prompt just keeps waiting. I found the below log from the ldap server side.
Log for successful search from client side
Jan 24 11:34:00 server3 slapd[11086]: conn=1012 fd=19 ACCEPT from IP=<CLIENT-IP>:22759 (IP=0.0.0.0:389)
Jan 24 11:34:00 server3 slapd[11086]: conn=1012 op=0 BIND dn="" method=128
Jan 24 11:34:00 server3 slapd[11086]: conn=1012 op=0 RESULT tag=97 err=0 text=
Jan 24 11:34:00 server3 slapd[11086]: conn=1012 op=1 SRCH base="<DOMAIN>" scope=2 deref=0 filter="(objectClass=*)"
Jan 24 11:34:00 server3 slapd[11086]: conn=1012 op=1 SRCH attr=ZZ
Jan 24 11:34:00 server3 slapd[11086]: conn=1012 op=1 SEARCH RESULT tag=101 err=0 nentries=6 text=
Jan 24 11:34:00 server3 slapd[11086]: conn=1012 op=2 UNBIND
Jan 24 11:34:00 server3 slapd[11086]: conn=1012 fd=19 closed
Log for unsuccessful ldap user login from client side
Jan 24 11:35:23 server3 slapd[11086]: conn=1013 fd=19 ACCEPT from IP=<CLIENT-IP>:53501 (IP=0.0.0.0:389)
Jan 24 11:35:23 server3 slapd[11086]: conn=1013 op=0 EXT oid=1.3.6.1.4.1.1466.20037
Jan 24 11:35:23 server3 slapd[11086]: conn=1013 op=0 STARTTLS
Jan 24 11:35:23 server3 slapd[11086]: conn=1013 op=0 RESULT oid= err=0 text=
Guide Link
http://cheenu-y2k.blogspot.in/2011/06/rhel6-openldap-server-configuratio