> If I use an ssh key to connect to computers owned by multiple organizations and I can't control how those servers are configured can I still use an SSH CA? N

> If I use an ssh key to connect to computers owned by multiple organizations and I can't control how those servers are configured can I still use an SSH CA? Not really. In general you need the same level of access for setting up the sshd host key, for setting up/enabling sshca: the server must trust the ca pub cert, and there's some configuration needed wrt principals (although AFAIK you can/should embed most of that in the certificate).