HP ProCurve 7000dl Series User Manual

12-12
Domain Name System (DNS) Services
Troubleshooting DNS
Note You can also start displaying the debug messages from any mode context with
the do command.
Then, have the DNS client again attempt to access the host. Track the router’s
activity. It should pass through the steps shown in Table 12-1. Determine where
the process breaks down and troubleshoot the problem accordingly.
Table 12-1. DNS Proxy Process
Step IP.DNS PROXY Messages Likely Problem If The
Message Does Not Appear
Likely Problem If The
Message Repeats
1. The router receives a
request to translate a
hostname.
Received request from
<DNS client>
DNS proxy is not enabled. The router cannot resolve
the hostname. (See Steps 2,
3, and 5 for possible causes.)
2. If the hostname is in the
local host table, the router
sends its IP address to the
client.
Serving reply for
“<hostname>” from host
database: <host A.B.C.D>
The host table does not
include the hostname.
——
3. If the hostname is not in
the table, the router
queries its own DNS
server.
Forwarding query for
“<hostname>” to <DNS
A.B.C.D>
You have not specified at
least one external DNS
server.
• The external server
cannot translate the
hostname.
• The router cannot reach
the external server.
4. If the server can translate
the name, the router
forwards the response to
the client.
• Received response from
server
• Transmitting response to
<DNS client>
• The external server
cannot translate the
hostname.
• The router cannot reach
the external server.
——
5. If the server cannot
translate the name, the
router appends the default
domain name to the
request and resends it.
Forwarding query for
“<hostname>.<default
domain name>” to <DNS
server A.B.C.D>
You have not configured a
default domain name.
• The external server
cannot translate the
hostname.
• The router cannot reach
the external server.
6. If the server can translate
the name, the router
forwards the response to
the client.
• Received response from
server
• Transmitting response to
<DNS client>
• The external server
cannot translate the
hostname.
• The router cannot reach
the external server.
——

HP ProCurve 7000dl Series Specifications

General

Brand	HP
Model	ProCurve 7000dl Series
Category	Network Router
Language	English