Error: Failed to install plugin / Plugin not found (packer init)

Error: Failed to install plugin / Plugin not found (packer init)

TL;DR

Packer cannot find the plugin your template requires. Run packer init in the template directory, verify the source address and version constraint in required_plugins, and check network access to the plugin registry.

The error

Error: Failed to install plugin
Plugin not found

Fix it

1. Run packer init (or packer init [dir]) in the directory containing your templates before packer build.

• Success check: plugins download into the Packer plugin directory.

1. Verify the required_plugins block: source must be a valid address like github.com/hashicorp/amazon, and version must match a released version.

• Success check: no typos in the source address; the version constraint is satisfiable.

1. Check network access from the build machine to github.com (plugin releases live there).

• Success check: curl -sI https://github.com succeeds.

1. In CI, cache ~/.packer.d/plugins between runs to avoid re-downloading.

• Success check: subsequent runs skip the download.

When to use this

You hit this on packer init or at build start when a required plugin cannot be installed.

When NOT to use this

Do not use this for Failed to initialize build "[builder]" (plugin installed but builder unknown) or for checksum mismatches on downloaded plugins.

Compatibility

Packer 1.7+ with the plugin framework (mandatory plugin installs since 1.10 for previously bundled builders).

Variants

• Error: Failed to install plugin naming a specific plugin and version
• Init succeeding locally but failing in CI (network or cache issue)

Root cause

Since Packer 1.10, builders that used to ship with Packer (like amazon-ebs) require explicit plugin installation. A missing packer init, a wrong source address, or no network produces this failure.

Edge cases

• packer plugins install github.com/hashicorp/amazon installs one plugin directly without a template; useful for debugging.
• Version constraints like >= 1.0.0, < 2.0.0 can fail if no release satisfies both. Loosen or pin explicitly.