CI "Connection timed out" - Fix Network Timeouts on Runners

By Kaveh Alemi·Latchkey

A connection attempt or transfer did not complete within the allotted time. The name resolved and the packets went out, but no timely response came back - a hallmark transient network failure.

What this error means

A download, clone, or API call hangs and then fails with Connection timed out, ETIMEDOUT, or curl: (28) Operation timed out. Re-running the job usually succeeds with no change.

CI log

curl: (28) Failed to connect to api.example.com port 443 after 30002 ms:
Connection timed out
# or
Error: connect ETIMEDOUT 140.82.112.3:443

Common causes

Transient network congestion or upstream slowness

A congested link or a briefly overloaded remote made the connection exceed its timeout. Nothing is wrong with the build - the network blipped.

A timeout that is too short for the transfer

Large downloads over a slow link can exceed a default client timeout even when the connection is healthy, producing a timeout that is really a slowness problem.

How to fix it

Retry with backoff

Transient timeouts almost always clear on a clean retry.

Terminal

curl --retry 5 --retry-delay 2 --retry-all-errors -fSL "$URL" -o out
# or wrap any command in a retry loop

Raise timeouts and reduce external calls

Increase the client connect/read timeout for large transfers.
Cache or mirror dependencies so fewer external connections are needed.
Pull from a geographically closer mirror to cut round-trip latency.

How to prevent it

Wrap network steps in bounded retry-with-backoff.
Cache/mirror dependencies to reduce external connections.
Set realistic timeouts for the size of the transfers.

Frequently asked questions

What causes ""Connection timed out""?