I\'m trying to run git clone without ssh checking the repository host\'s key. I can do it from ssh like that:
ssh -o UserKnownHostsFile=/dev/nul
I think that update git to an version >= 2.3 and use GIT_SSH_COMMAND="ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no" git clone user@host is the bet option, but if it not possible, @josh-lee gave a good option, but please, update your answer indenting the ssh config file.
Host host
HostName host
StrictHostKeyChecking no
UserKnownHostsFile /dev/null