Red Hat NETWORK PROXY 5.3.0 -, Installation Manual

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Host Not Found/Could Not Determine FQDN
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To obtain the status of Squid, run the command:
service squid status
If the administrator is not getting email from the RHN Proxy Server, confirm the correct email
addresses have been set for
traceback_mail
in
/etc/rhn/rhn.conf
.
6.5. Host Not Found/Could Not Determine FQDN
Because RHN configuration files rely exclusively on fully qualified domain names (FQDN), it is
imperative that key applications are able to resolve the name of the RHN Proxy Server into an IP
address. Red Hat Update Agent, Red Hat Network Registration Client, and the Apache Web server
are particularly prone to this problem with the RHN applications issuing errors of "host not found" and
the Web server stating "Could not determine the server's fully qualified domain name" upon failing to
start.
This problem typically originates from the
/etc/hosts
file. You may confirm this by examining
/etc/
nsswitch.conf
, which defines the methods and the order by which domain names are resolved.
Usually, the
/etc/hosts
file is checked first, followed by Network Information Service (NIS) if used,
followed by DNS. One of these has to succeed for the Apache Web server to start and the RHN client
applications to work.
To resolve this problem, identify the contents of the
/etc/hosts
file. It may look like this:
127.0.0.1 this_machine.example.com this_machine localhost.localdomain \
localhost
First, in a text editor, remove the offending machine information, like so:
127.0.0.1 localhost.localdomain.com localhost
Then, save the file and attempt to re-run the RHN client applications or the Apache Web server. If they
still fail, explicitly identify the IP address of the Proxy in the file, such as:
127.0.0.1 localhost.localdomain.com localhost
123.45.67.8 this_machine.example.com this_machine
Replace the value here with the actual IP address of the Proxy. This should resolve the problem.
Keep in mind, if the specific IP address is stipulated, the file will need to be updated when the machine
obtains a new address.
6.6. Connection Errors
If your are experiencing problems that you believe to be related to failed connections, follow these
measures:
• Confirm the correct package: