MEDIUM: make SO_REUSEPORT configurable
With Linux officially introducing SO_REUSEPORT support in 3.9 and
its mainstream adoption we have seen more people running into strange
SO_REUSEPORT related issues (a process management issue turning into
hard to diagnose problems because the kernel load-balances between the
new and an obsolete haproxy instance).
Also some people simply want the guarantee that the bind fails when
the old process is still bound.
This change makes SO_REUSEPORT configurable, introducing the command
line argument "-dR" and the noreuseport configuration directive.
A backport to 1.6 should be considered.
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 1a7114e..52e6cf4 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -578,6 +578,7 @@
- nopoll
- nosplice
- nogetaddrinfo
+ - noreuseport
- spread-checks
- server-state-base
- server-state-file
@@ -1130,6 +1131,10 @@
Disables the use of getaddrinfo(3) for name resolving. It is equivalent to
the command line argument "-dG". Deprecated gethostbyname(3) will be used.
+noreuseport
+ Disables the use of SO_REUSEPORT - see socket(7). It is equivalent to the
+ command line argument "-dR".
+
spread-checks <0..50, in percent>
Sometimes it is desirable to avoid sending agent and health checks to
servers at exact intervals, for instance when many logical servers are