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| author | Lennart Poettering <lennart@poettering.net> | 2021-11-22 12:20:05 +0100 |
|---|---|---|
| committer | Lennart Poettering <lennart@poettering.net> | 2021-11-22 22:33:24 +0100 |
| commit | a8d09063447568d87288a8e868fe386c1da7ce09 (patch) | |
| tree | b61ea5adbb8a517ecd64ce2407491eb193f67942 /man/resolved.conf.xml | |
| parent | c1b91f06b93ba29eafbf50f4858aedfb6ded4ff1 (diff) | |
| download | systemd-a8d09063447568d87288a8e868fe386c1da7ce09.tar.gz | |
resolved: add "proxy-only" stub on 127.0.0.54
This beefs up the DNS stub logic to listen on two IP addresses:
127.0.0.53 (as before) + 127.0.0.54 (new). When the latter is contact
our stub will operate in "bypass" mode only, i.e we'll try to pass DNS
requests as unmodified upstream as we can (and not do mDNS/LLMNR and
such, also no DNSSEC validation – but we'll still do DNS-over-TLS
wrapping).
This is supposed to be useful for container environments or tethering:
this stub could be exposed (via NAT redirect) to clients of this system
and we'll try to stay out of the way with doing too much DNS magic
ourselves, but still expose whatever the current DNS server is from
upstream under a stable address/port.
How to use this:
# iptables -t nat -I PREROUTING -p udp -i <interface> --dport 53 -j DNAT --to 127.0.0.54:53
# echo 1 > /proc/sys/net/ipv4/conf/<interface>/route_localnet
Diffstat (limited to 'man/resolved.conf.xml')
| -rw-r--r-- | man/resolved.conf.xml | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/man/resolved.conf.xml b/man/resolved.conf.xml index c1994604b9..f53af362e8 100644 --- a/man/resolved.conf.xml +++ b/man/resolved.conf.xml @@ -265,11 +265,13 @@ <varlistentry> <term><varname>DNSStubListener=</varname></term> - <listitem><para>Takes a boolean argument or one of <literal>udp</literal> and <literal>tcp</literal>. If - <literal>udp</literal>, a DNS stub resolver will listen for UDP requests on address 127.0.0.53 - port 53. If <literal>tcp</literal>, the stub will listen for TCP requests on the same address and port. If - <literal>yes</literal> (the default), the stub listens for both UDP and TCP requests. If <literal>no</literal>, the stub - listener is disabled.</para> + <listitem><para>Takes a boolean argument or one of <literal>udp</literal> and + <literal>tcp</literal>. If <literal>udp</literal>, a DNS stub resolver will listen for UDP requests + on addresses 127.0.0.53 and 127.0.0.54, port 53. If <literal>tcp</literal>, the stub will listen for + TCP requests on the same addresses and port. If <literal>yes</literal> (the default), the stub listens + for both UDP and TCP requests. If <literal>no</literal>, the stub listener is disabled.</para> + + <xi:include href="systemd-resolved.service.xml" xpointer="proxy-stub" /> <para>Note that the DNS stub listener is turned off implicitly when its listening address and port are already in use.</para></listitem> |