Summary

Builds fail during checkout, and the following two errors can be seen in the build logs: 

Git capability is not defined. Falling back to JGit, which is no longer supported. Define native git capability to get rid of this error.

ssh://<bitbucket>:<port>/<project>/<repo.git>: invalid privatekey: 

Environment

All supported versions of Bamboo.

Diagnosis

When reviewing the failed build logs, the following errors are present:

error	19-May-2023 10:58:38	Git capability is not defined. Falling back to JGit, which is no longer supported. Define native git capability to get rid of this error.

error	19-May-2023 10:58:38	Cannot fetch branch '<branch>' from 'ssh://<bitbucket>:<port>/<project>/<repository>.git' to source directory '<bamboo-agent-home>/xml-data/build-dir/_git-repositories-cache/<cache>'. ssh://<bitbucket>:<port>/<project>/<repository>.git: invalid privatekey: [B@5d42b0e

Cause

This happens when a native Git client is not installed in the remote agent (or in the Bamboo machine), which causes Bamboo to use its default JGit, which is known to have a few limitations.

Solution

Please make sure that a native Git client is installed on the agents and Bamboo machines, and that they are configured as capabilities:

• Defining a new version control capability
• Configuring agents
• Configuring capabilities

Once Git has been installed:

• Agents: either restart them to pick up the Git path automatically or set it manually by going to Bamboo Administration > Agents > open the agent's page > Add capability > Git.
  If you choose to restart the agent, you can check if the Git capability is now present under the Bamboo Administration > Agents > affected agent's page.
• Bamboo: go to Bamboo Administration > Server capabilities > click Detect server capabilities.