Installing and Administering Internet Services

108 Chapter 3

Conﬁguring and Administering the BIND Name Service

Troubleshooting the BIND Name Server

Name server records for div.inc.com, the delegated subdomain.

Authoritative answers can be found from:

walleye.div.inc.com inet address = 15.19.13.197

friday.div.inc.com inet address = 15.19.10.74

Address records for the name servers for div.inc.com.

• Dumping the name server database

Because the name server caches information, a database dump

can be searched for the NS and A records for the subdomain. If no

NS or A records exist, the parent server for the subdomain or the

root servers are not reachable. If NS and A records exist, check

their correctness. Then try pinging the addresses of the name

servers to see if they are reachable.

• Name server debugging output

Turn on debugging to level 1 and try to look up a name in the

domain. Check the debug output for name server retransmissions.

This will indicate which servers are not responding. Check that

the servers and their addresses are correct, if possible.

8. The local domain is not set. The local domain is used to complete

names that do not end with a dot. To set the local domain, either set

the host name (hostname) of the local system to a domain name

(without a trailing dot), or add a domain entry to

/etc/resolv.conf.

• nslookup

nslookup gives a warning that the local domain is not set.

• Name server debugging output

The debug output at level 1 shows names being looked up that are

not domain names.

• ping hostname

hostname is found only when it is a completely speciﬁed domain

name (with or without a trailing dot).

9. The /etc/nsswitch.conf ﬁle, if it exists, is not conﬁgured correctly.

If you want to query BIND before querying NIS or NIS+ or the

/etc/hosts ﬁle, make sure dns is listed ﬁrst on the hosts line. See

“Conﬁguring the Name Service Switch” on page 31.