Net::SSH::HostKeyMismatch Maybe cache

Hi,

I have a function that call Net::SSH and I got a Net::SSH::HostKeyMismatch problem. However I've clean known_hosts already and restart rails.

I guess this is a caching problem. How can I clean cache so it won't take old keys.

Thanks

    /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/verifiers/strict.rb:49:in `process_cache_miss'     /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/verifiers/strict.rb:38:in `verify'     /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/verifiers/lenient.rb:15:in `verify'     /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/transport/kex/diffie_hellman_group1_sha1.rb:165:in `verify_server_key'     /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/transport/kex/diffie_hellman_group1_sha1.rb:68:in `exchange_keys'     /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/transport/algorithms.rb:331:in `exchange_keys'     /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/transport/algorithms.rb:172:in `proceed!'     /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/transport/algorithms.rb:163:in `send_kexinit'     /usr/lib/ruby/gems/1.8/gems/net-ssh-2.0.3/lib/net/ssh/transport/algorithms.rb:118:in `accept_kexinit'