This patch excludes freebsd, osx and generic targets for this vtc.
Basic tcp checks performed by haproxy on a linux system leverage the
TCP_QUICKACK option which implies that the connection is never
established from the perspective of the backend server. On other systems
a regular tcp 3 way handshake is performed immediately followed by a
reset, which from the perspective of the server is an aborted connection.
When we run this regtest on FreeBSD (or anything other than linux) there
is a race condition in the server_thread() function of the vtc_server.c
file. If we receive the reset when we are in accept() then fd is -1 and
vtest calls vtc_fatal, failing the test.
Other checks specific reg-tests were excluded on FreeBSD, osx and
generic for the same reason, but were at the time documented as being
disabled because they used TCP_DEFER_ACCEPT. These commits are
15685c791 ("REGTEST: Exclude freebsd target for some reg tests") and
03c6ab0cb ("REGTEST: exclude osx and generic targets for
40be_2srv_odd_health_checks")
This test uses two sets of tcp-check connect port rules, with one
of the two ports being closed and expects the check to fail for both
backends at different steps. It aims at detecting regressions such as
the one fixed by 7df8ca62 (BUG/MEDIUM: tcp-check: unbreak multiple
connect rules again).
