Merge pull request #5137 from rgacogne/auth-fast-open

auth: Add TCP Fast Open support

diff --cc docs/markdown/authoritative/settings.md
Simple merge

diff --cc pdns/common_startup.cc
index 8eaa5b92c8dbe14061e7067af2507725296d7136,87bb65c223d701b498b65561d08f624668cc8ddf..954bce18010e736a2e74901c433c2d913b86f79e
--- 1/pdns/common_startup.cc
--- 2/pdns/common_startup.cc
+++ b/pdns/common_startup.cc
@@@ -193,9 -193,10 +193,11 @@@ void declareArguments(
  
    ::arg().setSwitch("outgoing-axfr-expand-alias", "Expand ALIAS records during outgoing AXFR")="no";
    ::arg().setSwitch("8bit-dns", "Allow 8bit dns queries")="no";
 +  ::arg().setSwitch("axfr-lower-serial", "Also AXFR a zone from a master with a lower serial")="no";
  
    ::arg().set("xfr-max-received-mbytes", "Maximum number of megabytes received from an incoming XFR")="100";
+ 
+   ::arg().set("tcp-fast-open", "Enable TCP Fast Open support on the listening sockets, using the supplied numerical value as the queue size")="0";
  }
  
  static time_t s_start=time(0);