ssh through another host

ssh_proxy_through_config

# Taken from this blog post 
# http://chrigl.de/blogentries/ssh-jump-host-without-nc-netcat
# Add the following to ~/.ssh/config, and adapt for your usage
#
# ProxyCommand ssh -A proxy_through_host -W %h:22
#  -A -- ssh-agent forwarding                                [optional]
#        (can be added to proxy host definition)
#  proxy_through_host -- hostname of server to proxy through [required]
#  -W %h:22 -- forward standard io to %h:22 (port 22)        [required]
#              %h is replaced with the host you're actually 
#              connecting to. This should be the internal ip

Host               proxy_through_host
   HostName        proxy.through.host.com

Host               foo 
   HostName        192.168.1.99
   ProxyCommand    ssh -A proxy_through_host -W %h:22

Host               bar 
   HostName        192.168.1.11
   ProxyCommand    ssh -A proxy_through_host -W %h:22