d7f6819161
Since the mworker rework in haproxy 3.1, the worker need to tell the master that it is ready. This is done using the sockpair protocol by sending a _send_status message to the master. It seems that the sockpair protocol is buggy on macOS because of a known issue around fd transfer documented in sendmsg(2): https://man.freebsd.org/cgi/man.cgi?sendmsg(2) BUGS section Because sendmsg() does not necessarily block until the data has been transferred, it is possible to transfer an open file descriptor across an AF_UNIX domain socket (see recv(2)), then close() it before it has actually been sent, the result being that the receiver gets a closed file descriptor. It is left to the application to implement an acknowledgment mechanism to prevent this from happening. Indeed the recv side of the sockpair is closed on the send side just after the send_fd_uxst(), which does not implement an acknowledgment mechanism. So the master might never recv the _send_status message. In order to implement an acknowledgment mechanism, a blocking read() is done before closing the recv fd on the sending side, so we are sure that the message was read on the other side. This was only reproduced on macOS, meaning the master CLI is also impacted on macOS. But no solution was found on macOS for it. Implementing an acknowledgment mechanism would complexify too much the protocol in non-blocking mode. The problem was reported in ticket #3045, reproduced and analyzed by @cognet. Must be backported as far as 3.1.
HAProxy
HAProxy is a free, very fast and reliable reverse-proxy offering high availability, load balancing, and proxying for TCP and HTTP-based applications.
Installation
The INSTALL file describes how to build HAProxy. A list of packages is also available on the wiki.
Getting help
The discourse and the mailing-list are available for questions or configuration assistance. You can also use the slack or IRC channel. Please don't use the issue tracker for these.
The issue tracker is only for bug reports or feature requests.
Documentation
The HAProxy documentation has been split into a number of different files for ease of use. It is available in text format as well as HTML. The wiki is also meant to replace the old architecture guide.
Please refer to the following files depending on what you're looking for:
- INSTALL for instructions on how to build and install HAProxy
- BRANCHES to understand the project's life cycle and what version to use
- LICENSE for the project's license
- CONTRIBUTING for the process to follow to submit contributions
The more detailed documentation is located into the doc/ directory:
- doc/intro.txt for a quick introduction on HAProxy
- doc/configuration.txt for the configuration's reference manual
- doc/lua.txt for the Lua's reference manual
- doc/SPOE.txt for how to use the SPOE engine
- doc/network-namespaces.txt for how to use network namespaces under Linux
- doc/management.txt for the management guide
- doc/regression-testing.txt for how to use the regression testing suite
- doc/peers.txt for the peers protocol reference
- doc/coding-style.txt for how to adopt HAProxy's coding style
- doc/internals for developer-specific documentation (not all up to date)
License
HAProxy is licensed under GPL 2 or any later version, the headers under LGPL 2.1. See the LICENSE file for a more detailed explanation.