Installing and Administering Internet Services
146 Chapter3
Configuring and Administering the BIND Name Service
Troubleshooting the BIND Name Server
datagram from 15.19.15.15 port 53, fd 6, len 51
send_msg -> 15.19.10.14 (UDP 7 4258) id=1
Debug turned OFF, Level 1
• In the first group of four lines, a query is received for
john.dept.inc.com. The query is forwarded to a root server,
ns.inc.ddn.mil at address 192.67.67.53
• In the second group of four lines, ns.nic.ddn.mil responded with NS
records for inc.com.
• In the third group of four lines, the inc.com server responded with NS
records for dept.inc.com.
• In the fourth group of four lines, the dept.inc.com server responded
with the address of john. The local server responds with the answer
to 15.19.10.14.
Following are detailed explanations of certain lines from the above
example.
Debug turned ON, Level 1
The name server was already running. The first level of debugging was
turned on with sig_named debug 1.
datagram from 15.19.10.14 port 4258, fd 6, len 35
This line shows the IP address of the host that generated the query, the
port that the request comes from, the file descriptor that the name server
received the query on, and the length of the query.
req: nlookup(john.dept.inc.com) ID 1 type=1
This message was logged from the routine that handles requests. Shown
are the name looked up, the packet ID (used to determine duplicate
requests), and the type (as defined in /usr/include/arpa/nameser.h).
Type 1 is an address query.
req: found 'john.dept.inc.com' as 'inc.com' (cname=0)
Since the server is authoritative for div.inc.com, it has an entry for
inc.com in its database. The only data at inc.com is the subdomain
entry for div. This line does not indicate what was found at inc.com.
Since the server sent the next query to a root name server, we conclude
that there were no NS records for inc.com. For more information,
including the domain for which the queried server is authoritative, check
Debug level 3. Debug levels are explained in “Name Server Debugging”
on page 137