systemd.dns-delegate

systemd

DNS Server Delegation Configuration

/etc/systemd/dns-delegate.d/*.dns-delegate, /run/systemd/dns-delegate.d/*.dns-delegate, /usr/local/lib/systemd/dns-delegate.d/*.dns-delegate, /usr/lib/systemd/dns-delegate.d/*.dns-delegate

Description

*.dns-delegate files may be used to delegate DNS lookups in specific domains to specific DNS servers. These files are read by systemd-resolved.service(8). Each such file defines a combination of one or more DNS servers and one or more DNS domains. Each such definition synthesizes a DNS lookup scope that ensure lookups below the specified domains are sent to the specified DNS servers, possibly in addition to any per-interface scopes and the global scope that systemd-resolved maintains anyway.

[Delegate] Section Options

DNS=
Takes one or more DNS server specifications, in the same syntax as the option of the same name in resolved.conf(5).

Domains=
Takes one or more domain name specifications, in the same syntax as the option of the same name in resolved.conf(5).

DefaultRoute=
Takes a boolean value, defaults to off. Controls whether this DNS server is a candidate for looking up records for which no better route exists.

FirewallMark=
Takes a 32 bit unsigned integer value. Controls the firewall mark of packets generated by the socket used to make DNS requests for this DNS delegate. This can be used in the firewall logic to filter packets from this socket. This sets the SO_MARK socket option. See iptables(8) for details.

Examples

# /etc/systemd/dns-delegate.d/foobar.dns-delegate
[Delegate]
DNS=203.0.113.47
Domains=foobar.com
FirewallMark=42

This ensures lookups of foobar.com and any domains below it are directed to DNS server 203.0.113.47 and any packets related to this lookup have a firewall mark set to 42.