Exit Code 100 in CI: apt-get and Package Manager Failures
Exit code 100 is best known from apt/apt-get, which returns it when a package operation fails.
A step exiting 100 in a Debian/Ubuntu pipeline almost always came from apt failing to install or configure a package.
What it means
apt and apt-get use exit code 100 for package errors: a package that cannot be found, an unmet dependency, or a held dpkg lock. The meaning is tool-specific to apt.
Common causes
Unable to locate packagedue to a stale index (noapt-get update).- A held dpkg lock from a concurrent process.
- A repository that was temporarily unreachable.
How to fix it
Run apt-get update before install, pin the package name/version, and avoid concurrent apt runs. A transient mirror outage clears on retry; Latchkey can install a known-missing system package and retry the step automatically.
Reading exit codes in CI
- A shell reports
128 + Nwhen a process is terminated by signal N: 137 is SIGKILL (usually the out-of-memory killer), 143 is SIGTERM, 130 is SIGINT. - Exit code 137 in a container almost always means the kernel killed it for memory. Nothing in the application log will explain it.
- A pipeline reports the exit status of its LAST command unless
pipefailis set, which is how a failing command piped toteeproduces a green build. - Some tools use non-zero codes for non-failure outcomes. Check the tool documentation before treating any non-zero code as an error.
Frequently asked questions
Exit Code 100 in CI: apt-get and Package Manager Failures?
A step exiting 100 in a Debian/Ubuntu pipeline almost always came from apt failing to install or configure a package.
What it means?
apt and apt-get use exit code 100 for package errors: a package that cannot be found, an unmet dependency, or a held dpkg lock. The meaning is tool-specific to apt.
How to fix it?
Run apt-get update before install, pin the package name/version, and avoid concurrent apt runs. A transient mirror outage clears on retry; Latchkey can install a known-missing system package and retry the step automatically.
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