From 5aff67893b993364cf48edbb927661315927f00d Mon Sep 17 00:00:00 2001 From: Christian Poessinger Date: Sun, 15 Dec 2019 15:43:37 +0100 Subject: dns-forwarding: add negative-ttl option --- docs/services/dns-forwarding.rst | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'docs/services') diff --git a/docs/services/dns-forwarding.rst b/docs/services/dns-forwarding.rst index e98d7f6b..bd05395e 100644 --- a/docs/services/dns-forwarding.rst +++ b/docs/services/dns-forwarding.rst @@ -87,6 +87,14 @@ use this file to add resolvers to assigned addresses. Maximum number of DNS cache entries. 1 million per CPU core will generally suffice for most installations. +.. cfgcmd:: set service dns forwarding negative-ttl + +A query for which there is authoritatively no answer is cached to quickly deny +a record's existence later on, without putting a heavy load on the remote +server. In practice, caches can become saturated with hundreds of thousands of +hosts which are tried only once. This setting, which defaults to 3600 seconds, +puts a maximum on the amount of time negative entries are cached. + Example ======= -- cgit v1.2.3