Add ReusePort config to confighttp by sinkingpoint · Pull Request #14058 · open-telemetry/opentelemetry-collector

sinkingpoint · 2025-10-21T09:23:00Z

Description

This adds in a new field, ReusePort that, if set, sets the SO_REUSEPORT socket option on the listener port. If we're on non unix, this errors out instead as AFAIK SO_REUSEPORT isn't available. Cursory googling says that SO_REUSEADDR might work, but I don't have a windows machine to test on.

Link to tracking issue

#14046

Testing

We add a new test, TestServerReusePort which checks the behaviour of both setting and unsetting the ReusePort config with the expectation of an error if it isn't set and it not erroring when binding twice to the same port

codecov · 2025-10-21T09:50:55Z

Codecov Report

❌ Patch coverage is 66.66667% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.29%. Comparing base (22a5e61) to head (c90e0fb).

Files with missing lines	Patch %	Lines
config/confignet/confignet.go	33.33%	2 Missing and 2 partials ⚠️
config/confignet/listen_config_unix.go	83.33%	1 Missing and 1 partial ⚠️

❌ Your patch check has failed because the patch coverage (66.66%) is below the target coverage (95.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #14058      +/-   ##
==========================================
- Coverage   91.31%   91.29%   -0.03%     
==========================================
  Files         699      700       +1     
  Lines       44939    44956      +17     
==========================================
+ Hits        41036    41041       +5     
- Misses       2759     2766       +7     
- Partials     1144     1149       +5

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

sinkingpoint · 2025-10-21T10:26:53Z

Contrib test failure fixed here: open-telemetry/opentelemetry-collector-contrib#43681

Without a valid `runCtx`, anything that attempts to use the context segfaults. In open-telemetry/opentelemetry-collector#14058 I am using the context, so this test borks. This adds the runCtx to fix it. Signed-off-by: sinkingpoint <colin@quirl.co.nz>

#### Description Without a valid `runCtx`, anything that attempts to use the context segfaults. In open-telemetry/opentelemetry-collector#14058 I am using the context, so this test borks. This adds the runCtx to fix it.  #### Link to tracking issue open-telemetry/opentelemetry-collector#14058  #### Testing  #### Documentation  Signed-off-by: sinkingpoint <colin@quirl.co.nz>

axw · 2025-10-22T01:28:34Z

Should we have this for configgrpc too? And non-HTTP/gRPC?

I'm wondering if we should make a breaking change to confighttp.ServerConfig to use confignet.AddrConfig, similar to configgrpc:

opentelemetry-collector/config/configgrpc/configgrpc.go

Line 176 in c657d5d

NetAddr confignet.AddrConfig `mapstructure:",squash"`

Then we could add ReusePort to confignet.AddrConfig and have it in one place.

(Not necessarily all in this PR, just thinking out loud about how to generalise this change.)

sinkingpoint · 2025-10-22T08:27:07Z

Should we have this for configgrpc too? And non-HTTP/gRPC?

I was going to do those in a separate PR, but rely on "A little copying is better than a little dependency" and just copy the same config changes across. Breaking changes scare me

axw · 2025-10-22T10:19:13Z

@sinkingpoint 👍 that seems fine, we can always make a breaking change independently if desired.

sinkingpoint · 2025-10-22T13:02:47Z

Actually, looking at it a bit more: configgrpc provides .Serve(net.Listener), and all the uses in the contrib repo actually use confighttps ToListener to create the listener to pass into that, so this handles both

dmathieu · 2025-10-22T13:18:01Z

+
+func TestServerReusePort(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping test: SO_REUSEPORT is not supported on windows")


Could you add a test checking that we do get an error when trying to use SoReuse on windows?

This adds in a new field, `ReusePort` that, if set, sets the SO_REUSEPORT socket option on the listener port. If we're on non unix, this errors out instead as AFAIK SO_REUSEPORT isn't available. Cursory testing says that SO_REUSEADDR _might_ work, but I don't have a windows machine to test on. Signed-off-by: sinkingpoint <colin@quirl.co.nz>

dmathieu · 2025-10-22T13:50:18Z

Could you avoid force-pushing? That breaks the GitHub review interface.

Signed-off-by: sinkingpoint <colin@quirl.co.nz>

sinkingpoint · 2025-10-22T13:57:32Z

Apologies 😬 I think I've fixed it up now anyway

axw · 2025-10-23T07:21:41Z

Actually, looking at it a bit more: configgrpc provides .Serve(net.Listener), and all the uses in the contrib repo actually use confighttps ToListener to create the listener to pass into that, so this handles both

Where did you see that being done? I found the stef receiver is not using confighttp, for example: https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/e3f1205a034ff05c1c31e1e1b84a8bf735563d91/receiver/stefreceiver/stef.go#L57-L77

sinkingpoint · 2025-10-23T08:24:01Z

Oh hrm.. I checked several, like https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/receiver/skywalkingreceiver/skywalking_receiver.go#L144 , but you're right - missed the ones that use confignet. Want me to update that here? Or put in a seperate PR?

axw · 2025-10-23T08:28:11Z

Ah I see. That receiver probably should be updated, but I digress

A separate PR sounds good to me, maybe change the description so the issue doesn't get closed when this PR is merged

axw · 2026-01-06T00:09:58Z

Done @axw . Do you have an ETA on #14248 ? confighttp was the one I really cared about in the first place

Thank you 🙏

I don't have an ETA, just waiting on a maintainer to merge it - I imagine many of whom are coming back from time off.

As per PR comments, this moves things around so that listen_config_other becomes listen_config_unix, and listen_config_windows becomes listen_config_other, with appropriate build gating. Signed-off-by: sinkingpoint <colin@quirl.co.nz>

…tor into sinkingpoint/so-reuse-port

sinkingpoint · 2026-01-15T15:47:39Z

@bogdandrutu @dmitryax Does this look OK now?

evan-bradley

Thanks for your patience with the long review cycle @sinkingpoint.

github-actions · 2026-02-13T04:01:01Z

This PR was marked stale due to lack of activity. It will be closed in 14 days.

…tor into sinkingpoint/so-reuse-port

Signed-off-by: sinkingpoint <colin@quirl.co.nz>

This changes the if runtime.GOOS == "windows" { to properly match the updated build tags Signed-off-by: sinkingpoint <colin@quirl.co.nz>

sinkingpoint · 2026-02-19T15:49:20Z

@evan-bradley Can I get another look from you when you get a sec?

evan-bradley

Thanks @sinkingpoint. I'd like to get approvals from a few other approvers/maintainers since this is a stable module and we can't revert this change once it's released.

github-actions · 2026-03-06T03:54:15Z

This PR was marked stale due to lack of activity. It will be closed in 14 days.

github-actions · 2026-03-22T04:00:40Z

This PR was marked stale due to lack of activity. It will be closed in 14 days.

axw · 2026-04-02T03:07:19Z

@sinkingpoint I hope you don't mind, I took the liberty of addressing @evan-bradley's comments and pushing to your branch

github-actions · 2026-04-19T04:15:17Z

This PR was marked stale due to lack of activity. It will be closed in 14 days.

sinkingpoint requested a review from a team as a code owner October 21, 2025 09:23

sinkingpoint requested a review from dmitryax October 21, 2025 09:23

sinkingpoint force-pushed the sinkingpoint/so-reuse-port branch 5 times, most recently from 636ae93 to 344b948 Compare October 21, 2025 09:39

sinkingpoint force-pushed the sinkingpoint/so-reuse-port branch from 344b948 to bac556b Compare October 21, 2025 10:20

sinkingpoint mentioned this pull request Oct 21, 2025

[chore] Pass runCtx into supervisor Health check test open-telemetry/opentelemetry-collector-contrib#43681

Merged

sinkingpoint force-pushed the sinkingpoint/so-reuse-port branch from bac556b to 8f6079d Compare October 22, 2025 12:55

dmathieu reviewed Oct 22, 2025

View reviewed changes

sinkingpoint force-pushed the sinkingpoint/so-reuse-port branch from 8f6079d to 3d1484b Compare October 22, 2025 13:49

sinkingpoint force-pushed the sinkingpoint/so-reuse-port branch from 3d1484b to e063074 Compare October 22, 2025 13:49

ci fix

4285bb8

Signed-off-by: sinkingpoint <colin@quirl.co.nz>

dmathieu approved these changes Oct 22, 2025

View reviewed changes

bogdandrutu reviewed Jan 8, 2026

View reviewed changes

Comment thread config/confignet/listen_config_other.go Outdated

sinkingpoint added 2 commits January 12, 2026 14:37

Shuffle listen_config files

dc599af

As per PR comments, this moves things around so that listen_config_other becomes listen_config_unix, and listen_config_windows becomes listen_config_other, with appropriate build gating. Signed-off-by: sinkingpoint <colin@quirl.co.nz>

Merge branch 'main' of github.com:open-telemetry/opentelemetry-collec…

8b90b76

…tor into sinkingpoint/so-reuse-port

evan-bradley removed the ready-to-merge Code review completed; ready to merge by maintainers label Jan 26, 2026

evan-bradley reviewed Jan 26, 2026

View reviewed changes

Comment thread config/confignet/confignet_test.go Outdated

Comment thread config/confignet/listen_config_unix.go

Comment thread config/confignet/confignet.go Outdated

Comment thread config/confignet/confignet.go

github-actions Bot added the Stale label Feb 13, 2026

sinkingpoint added 4 commits February 19, 2026 09:36

Merge branch 'main' of github.com:open-telemetry/opentelemetry-collec…

1930e65

…tor into sinkingpoint/so-reuse-port

Document reuse-port setting more

1ac28b2

Signed-off-by: sinkingpoint <colin@quirl.co.nz>

Fix spell check on confignet readme

f5ef1d5

Signed-off-by: sinkingpoint <colin@quirl.co.nz>

Update ReusePort tests to properly scope checks

1e6b994

This changes the if runtime.GOOS == "windows" { to properly match the updated build tags Signed-off-by: sinkingpoint <colin@quirl.co.nz>

evan-bradley removed the Stale label Feb 19, 2026

evan-bradley approved these changes Feb 19, 2026

View reviewed changes

Comment thread config/confignet/README.md Outdated

Comment thread config/confignet/confignet_test.go Outdated

github-actions Bot added Stale and removed Stale labels Mar 6, 2026

github-actions Bot added the Stale label Mar 22, 2026

axw added 2 commits April 2, 2026 11:03

Add SO_REUSEPORT to cspell.json

27e7524

Fix error assertion

c70d0d8

Merge branch 'main' into sinkingpoint/so-reuse-port

1193834

axw removed the Stale label Apr 2, 2026

github-actions Bot added the Stale label Apr 19, 2026

Merge branch 'main' into sinkingpoint/so-reuse-port

c90e0fb

axw removed the Stale label Apr 20, 2026

Conversation

sinkingpoint commented Oct 21, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Description

Link to tracking issue

Testing

Uh oh!

codecov Bot commented Oct 21, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Codecov Report

Uh oh!

sinkingpoint commented Oct 21, 2025

Uh oh!

axw commented Oct 22, 2025

Uh oh!

sinkingpoint commented Oct 22, 2025

Uh oh!

axw commented Oct 22, 2025

Uh oh!

sinkingpoint commented Oct 22, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

dmathieu Oct 22, 2025

Choose a reason for hiding this comment

Uh oh!

Uh oh!

dmathieu commented Oct 22, 2025

Uh oh!

sinkingpoint commented Oct 22, 2025

Uh oh!

axw commented Oct 23, 2025

Uh oh!

sinkingpoint commented Oct 23, 2025

Uh oh!

axw commented Oct 23, 2025

Uh oh!

axw commented Jan 6, 2026

Uh oh!

Uh oh!

sinkingpoint commented Jan 15, 2026

Uh oh!

evan-bradley left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

github-actions Bot commented Feb 13, 2026

Uh oh!

sinkingpoint commented Feb 19, 2026

Uh oh!

evan-bradley left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

github-actions Bot commented Mar 6, 2026

Uh oh!

github-actions Bot commented Mar 22, 2026

Uh oh!

axw commented Apr 2, 2026

Uh oh!

github-actions Bot commented Apr 19, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

6 participants

sinkingpoint commented Oct 21, 2025 •

edited

Loading

codecov Bot commented Oct 21, 2025 •

edited

Loading

sinkingpoint commented Oct 22, 2025 •

edited

Loading