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Aurelien DARRAGON c16eba8183 BUG/MEDIUM: server/dns: preserve server's port upon resolution timeout or error
@boi4 reported in GH #2578 that since 3.0-dev1 for servers with address
learned from A/AAAA records after a DNS flap server would be put out of
maintenance with proper address but with invalid port (== 0), making it
unusable and causing tcp checks to fail:

[NOTICE]   (1) : Loading success.
[WARNING]  (8) : Server mybackend/myserver1 is going DOWN for maintenance (DNS refused status). 0 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue.
[ALERT]    (8) : backend 'mybackend' has no server available!
[WARNING]  (8) : mybackend/myserver1: IP changed from '(none)' to '127.0.0.1' by 'myresolver/ns1'.
[WARNING]  (8) : Server mybackend/myserver1 ('myhost') is UP/READY (resolves again).
[WARNING]  (8) : Server mybackend/myserver1 administratively READY thanks to valid DNS answer.
[WARNING]  (8) : Server mybackend/myserver1 is DOWN, reason: Layer4 connection problem, info: "Connection refused", check duration: 0ms. 0 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue.

@boi4 also mentioned that this used to work fine before.

Willy suggested that this regression may have been introduced by 64c9c8e
("BUG/MINOR: server/dns: use server_set_inetaddr() to unset srv addr from DNS")

Turns out he was right! Indeed, in 64c9c8e we systematically memset the
whole server_inetaddr struct (which contains both the requested server's
addr and port planned for atomic update) instead of only memsetting the
addr part of the structure: except when SRV records are involved (SRV
records provide both the address and the port unlike A or AAAA records),
we must not reset the server's port upon DNS errors because the port may
have been provided at config time and we don't want to lose its value.

Big thanks to @boi4 for his well-documented issue that really helped us to
pinpoint the bug right on time for the dev-13 release.

No backport needed (unless 64c9c8e gets backported).
2024-05-24 15:29:48 +02:00
.github CI: drop asan.log umbrella completely 2024-05-13 11:36:36 +02:00
addons MINOR: stats: define stats-file output format support 2024-04-26 10:20:57 +02:00
admin BUILD: address a few remaining calloc(size, n) cases 2024-02-10 11:37:27 +01:00
dev DEV: flags/peers: Decode PEER and PEERS flags 2024-04-25 18:29:58 +02:00
doc MINOR: server: define pool-conn-name keyword 2024-05-24 14:36:31 +02:00
examples CLEANUP: assorted typo fixes in the code and comments 2023-11-23 16:23:14 +01:00
include MEDIUM: connection: use pool-conn-name instead of sni on reuse 2024-05-24 14:47:21 +02:00
reg-tests MAJOR: spoe: Let the SPOE back into the game 2024-05-22 09:04:38 +02:00
scripts CI: scripts/buil-ssl: cleanup the boringssl and quictls build 2024-05-23 16:54:30 +02:00
src BUG/MEDIUM: server/dns: preserve server's port upon resolution timeout or error 2024-05-24 15:29:48 +02:00
tests MINOR: ist: define iststrip() new function 2024-04-26 11:29:25 +02:00
.cirrus.yml CI: cirrus-ci: display gdb bt if any 2023-09-22 08:28:30 +02:00
.gitattributes MINOR: Configure the cpp userdiff driver for *.[ch] in .gitattributes 2021-02-22 18:17:57 +01:00
.gitignore CONTRIB: Add vi file extensions to .gitignore 2023-06-02 18:14:34 +02:00
.mailmap DOC: update Tim's address in .mailmap 2021-09-16 09:14:14 +02:00
.travis.yml CI: travis-ci: temporarily disable arm64 builds 2021-08-07 07:28:15 +02:00
BRANCHES DOC: fix some spelling issues over multiple files 2021-01-08 14:53:47 +01:00
BSDmakefile BUILD: makefile: commit the tiny FreeBSD makefile stub 2023-05-24 17:17:36 +02:00
CHANGELOG [RELEASE] Released version 3.0-dev12 2024-05-18 16:51:23 +02:00
CONTRIBUTING CLEANUP: assorted typo fixes in the code and comments 2021-08-16 12:37:59 +02:00
INSTALL DOC: install: clarify the build process by splitting it into subsections 2024-04-11 18:02:26 +02:00
LICENSE LICENSE: add licence exception for OpenSSL 2012-09-07 13:52:26 +02:00
MAINTAINERS MAJOR: spoe: Let the SPOE back into the game 2024-05-22 09:04:38 +02:00
Makefile REORG: stats: define stats-proxy source module 2024-05-02 16:42:36 +02:00
README DOC: create a BRANCHES file to explain the life cycle 2019-06-15 22:00:14 +02:00
SUBVERS BUILD: use format tags in VERDATE and SUBVERS files 2013-12-10 11:22:49 +01:00
VERDATE [RELEASE] Released version 3.0-dev12 2024-05-18 16:51:23 +02:00
VERSION [RELEASE] Released version 3.0-dev12 2024-05-18 16:51:23 +02:00

The HAProxy documentation has been split into a number of different files for
ease of use.

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)