Controls how Git plugin verifies the keys presented by the host during SSH connecting.

Known hosts file (default)
Verifies all host keys using the known_hosts file.
Accept first connection
Automatically adds host keys to the known_hosts file if the host has not been seen before, and does not allow connections to previously-seen hosts with modified keys.
- Note that when using ephemeral agents (ex. cloud agents), this strategy is essentially equivalent to No verification because it uses the known_hosts file on the agent. To avoid this, you can pre-configure known_hosts with all relevant hosts when creating the images or templates used to define your agents, or use the Manually provided keys or Known hosts file strategies.
- OpenSSH version 7.6 or higher is required to use this option with command line Git.
Manually provided keys
Verifies all host keys using a set of keys manually configured here.
No verification (not recommended)
Does not verify host keys at all.