7.3. Hostname resolution (DNS)

Charybdis uses solely DNS for all hostname/address lookups (no /etc/hosts or anything else). The DNS servers are taken from /etc/resolv.conf. If this file does not exist or no valid IP addresses are listed in it, the local host (127.0.0.1) is used. (Note that the latter part did not work in older versions of Charybdis.)

IPv4 as well as IPv6 DNS servers are supported, but it is not possible to use both IPv4 and IPv6 in /etc/resolv.conf.

For both security and performance reasons, it is recommended that a caching nameserver such as BIND be run on the same machine as Charybdis and that /etc/resolv.conf only list 127.0.0.1.