I'm not familiar with clusterssh, but assuming that it passes flags to ssh you can add `-o StrictHostKeyChecking=no`. Of course, the parameter does what it say

I'm not familiar with clusterssh, but assuming that it passes flags to ssh you can add `-o StrictHostKeyChecking=no`. Of course, the parameter does what it says, but the security implications are really the same as for blindly yessing your way through. The best is to pre-populate your hosts file using ssh-keyscan.