When we try out the public key authentication with karaf shell login. We follow the documentation
Not only the documentation is not relevant ( There are docs with container and fabric and they should not appear in 7.x, but that's a different jira with doc), the default keys.properties admin role missing 'ssh' causing bin/client not to work.
etc/keys.properties
g\:admingroup = group,admin,manager,viewer,systembundles
Request to change to
g\:admingroup = group,admin,manager,viewer,systembundles,ssh