10.5.34. HostnameLookups
HostnameLookups
can be set to on
, off
, or double
. If HostnameLookups
is set to on
, the server automatically resolves the IP address for each connection. Resolving the IP address means that the server makes one or more connections to a DNS server, adding processing overhead. If HostnameLookups
is set to double
, the server performs a double-reverse DNS look up adding even more processing overhead.
To conserve resources on the server,
HostnameLookups
is set to off
by default.
If hostnames are required in server log files, consider running one of the many log analyzer tools that perform the DNS lookups more efficiently and in bulk when rotating the Web server log files.