Finally I raised a TAC case and they provided a solution for it. Actually when I changed the Leading IP via mdsconfig, it didn't update all the directory. Below are the steps I performed on new MDS
# $MDSDIR/bin/mdscmd change-mds-ip <Old IP address> <New IP address> ipv4 -x
For example, to change the IP from 192.168.1.1 to 10.1.1.1, run:
# $MDSDIR/bin/mdscmd change-mds-ip 192.168.1.1 10.1.1.1 ipv4 -x
Then run below psql queries and check in mdss.txt and cpnetwork.txt that new IP is updated on the MDS object in database:
#psql_client -c "select fwset from dleobjectderef_data where cpmitable='mdss' and not deleted and dlesession=0" -o mdss.txt cpm postgres
#psql_client -c "select name, ipaddress4 from cpnetworkobject_data where not deleted and dlesession=0" -o cpnetwork.txt cpm postgres