By enabling this option you can perform name lookups on any IP addresses found in the logfile.
'DNS Cachefile' specifies the file, the resolved URLs are cached. If an absolute path is not given as part of the filename (ie: starts with a leading '/' or 'c:\'), then the name is relative to the default output directory. However if the 'Clear target directory' option is enabled, the DNS Cachefile should be saved in another directory, because otherwise it would also be deleted everytime the Webalizer is run.
'DNS Child-Processes' allows you to specify how many 'children' processes are run to perform DNS lookups to create or update the DNS cache file. The number of children processes to run may be anywhere from 1 to 100, however a large number may effect normal system operations. Reasonable values should be between 5 and 20.
Please note: The original Windows version of the Webalizer (Version 2.01-10) is not able to perform DNS-lookups. To do so you have to install a Webalizer version from http://www.medasys-lille.com/webalizer/ or http://www.stonesteps.ca/projects/webalizer/. The plus-version of the GUI has the Stone Steps Webalizer included, making it possible to perform reverse DNS-lookups.