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Reuse SSH connections with ControlMaster

harmlessSSHalle
Adjust the values, the command updates live
user@server
ssh -o ControlMaster=auto -o ControlPath=~/.ssh/cm-%C -o ControlPersist=10m webuser@server.example.com

The first connection creates a control socket that all further connections to the same target go through. Additional sessions, scp and rsync therefore start without a new handshake and without a second 2FA prompt. After logging out, ControlPersist keeps the connection open for another ten minutes.

Note: For permanent use, the three options belong in a Host block in ~/.ssh/config. ssh -O exit benutzer@host closes the master connection.

Also searched as

  • ssh connection multiplexing
  • ssh controlmaster controlpersist
  • speed up repeated ssh connections

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