ypcat ipnodes not working

When I try to get ipnodes it says "no such map in server's NIS domain"
but for other maps its working.
Then my query is if map is not there why it shows the entry when I "ypcat -x"

adroit:/home/seo/hitendra 37 ] ypcat -x
Use "passwd"    for map "passwd.byname"
Use "group"     for map "group.byname"
Use "networks"  for map "networks.byaddr"
Use "hosts"     for map "hosts.byname"
Use "ipnodes"   for map "ipnodes.byname"
Use "protocols" for map "protocols.bynumber"
Use "services"  for map "services.byname"
Use "aliases"   for map "mail.aliases"
Use "ethers"    for map "ethers.byname"
adroit:/home/seo/hitendra 38 ] ypcat networks
loopback        127
arpanet         10              arpa
adroit:/home/seo/hitendra 39 ] ypcat ipnodes
ypcat:  no such map in server's NIS domain
adroit:/home/seo/hitendra 40 ]

You have no ipnodes map on your nis server.

Because "ypcat -x" isn't querying anything on your nis server. It simply dumps the content of the /var/yp/nicknames file.