DNS Settings

DNS is the system used to associate standard IP addresses with host names. DNS lookup involves computational and network costs as it requires talking to a DNS server to resolve a host name to it's IP address. To optimize performance, consider the following options:

• Enable DNS caching.

  DNS Caching is enabled by choosing the Configure DNS Cache link under the Preferences tab of the Server Manager. Select the Enabled radio button for DNS caching.

• Log only client IP addresses rather than client DNS names.

  Client DNS name logging is disabled by choosing the Set Access Log Preferences link under the Server Status tab of the Server Manager. Select the IP Addresses radio button to log IP addresses rather than client host names.

• Disable reverse DNS.

  Reverse DNS translates IP addresses into host names. Reverse DNS is disabled by choosing the Configure System Preferences link under the Preferences tab of the Server Manager. Select the No radio button to disable reverse DNS.

• Avoid access control based on client host names

  When possible, use clients’ IP addresses instead of host names in access control statements.