C a u t i o n
Troubleshooting DNS
When the ProCurve Secure Router cannot correctly resolve domain names,
you can monitor DNS error messages to pinpoint the source of the problem.
You should be able to interpret DNS messages well enough to track the DNS
process and determine where problems arise.
Enabling DNS debug messages can seriously compromise the network as the
router is forced to debug the many DNS requests arriving from clients.
Before enabling debug messages, you can check for some of the most common
problems described in the next section.
You should also determine that all connections are up and that hosts can ping
each other. In other words, you should be certain that basic connectivity is
not the root of the problem.
Process
First, determine whether the router is acting as a DNS client or a DNS server.
Then activate the corresponding debug messages.
The ProCurve Secure Router acts as a DNS server when it:
receives DNS requests from hosts on its network
checks its host table for a matching entry
forwards queries to an external DNS server
forwards the IP address for a hostname to a DNS client
The ProCurve Secure Router acts as a DNS client when it:
sends a query to an external name server on its own behalf
Debugging DNS Server Activity
To monitor the router's activity as it receives, forwards, and responds to DNS
requests, enter the following enable mode context command:
ProCurve# debug ip dns-proxy
Domain Name System (DNS) Services
Troubleshooting DNS
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