useful ssh configurations

sshconfig

Host *
    ControlMaster auto
    ControlPath ~/.ssh/sockets/%C
    ControlPersist 120
    IdentityFile ~/.ssh/id_rsa
    
Host *
    ControlMaster auto
    ControlPath ~/.ssh/sockets/%C
    ControlPersist 120
    ServerAliveInterval 120
    IdentityFile ~/.ssh/id_rsa
    AddKeysToAgent yes
    
Host bastion
    Hostname bastion.com

# uses wildcard for host alias
# invoke subsystem proxy through proxy command
# i.e. ssh into 'some-proxy:8022' and call 'proxy' subsystem on some-proxy
Host *.example.com *.other.com
    HostName %h
    Port 22
    ProxyCommand ssh -p 8022 %r@some-proxy -s proxy:%h:%p
    
# for proxy command sugar syntax
Host foo
    ProxyJump bastion # same as using -W which is -N -T
    Hostname example.com
    Port 22
    User ubuntu