f47d80402a
In master-worker mode the master CLI proxy (mworker_proxy) has a hardcoded maxconn of 10. When a client connects to the master CLI socket and issues a command that gets forwarded to an unresponsive worker (e.g. one that is stuck or very slow), the connection hangs waiting for the worker's response. If the client then disconnects (timeout, Ctrl-C, etc.), the connection slot is never released because the client-side FIN is never acknowledged by the unresponsive worker. After 10 such leaked slots the master CLI socket becomes completely unreachable, returning "Resource temporarily unavailable" to any new connection attempt. In containerized deployments this means readiness probes start failing and the pod gets restarted. The fix adds a timeout server-fin of 1s to the mworker_proxy. When the client disconnects while waiting for a worker response, this timeout ensures the dangling backend connection is cleaned up after 1s, freeing the connection slot. This does not affect normal CLI operations since the timeout only starts after the client has already closed its side of the connection. A regression test is included that blocks the worker CLI thread using "debug dev delay" with nbthread 1, fills all 10 master CLI slots, waits for client-side timeouts, then verifies a new connection still succeeds. This fixes GH issue #3351. This should be backported to all stable branches. Co-authored-by: Martin Strenge <github@trixer.net> Co-authored-by: William Lallemand <wlallemand@haproxy.com>
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.