Screen is a utility that allows one console user to share their terminal with another. This is an excellent solution for training or administrative knowledge/task sharing.
Most distros have this installed by default, on Praxis you many need to:
root@host # emerge -pv screen [ebuild N ] app-misc/screen-4.0.3 USE="-debug multiuser -nethack pam (-selinux)" 821 kB
Screen keeps a configuration in
This can control the meta-command characters and other screen defaults.
May want to adjust this file following these snippets.
defscrollback 5000 multiuser on startup_message on
Screen to Resume / Place-Holder
In this scenario screen can be use to create a session that one can disconnect from and then re-connect to.
Nice for usage of low-quality links or when switching locations/networks.
Simply run screen, maybe give it a name.
Then when you detach or the connection drops you can reconnect.
-S argument to name the session
# screen -S foobar # echo $TERM
You can detach using Ctrl+a, Ctrl+d, or if the SSH connection drops you will be detached as well. To re-attach to that session simply -r with its identifier or name.
In screen the command Ctrl+a H will enable logging to
screenlog.# in the current working directory.
This is useful for session logging, or for perforing long system maintenance/troubleshooting to be able to replay.
root@host # screen -list 20145.pts-0.carbon (Attached) 20232.foobar (Attached) 2 Sockets in /var/run/screen/S-root. # screen -r 1234.pts-0.root # screen -r foobar
This is useful for UserA to share the screen with UserB in a teacher-student or mutual shared work-space. The first example is shared work-space, the second is teacher-student style.
First admin will login/ssh-in/what-ever to access a terminal and start screen with a session name (-S).
The second admin/worker/user will connect and then use
-x to attach to the same.
root@host # screen -S watch_me
This example is for teacher-student style, where the studet session is view-only. Multiple view-only session can be attached to this multi-user session.
root@host # screen -S watch_me root@host # Ctrl+a :multiuser on root@host # Ctrl+a :acladd UserA root@host # Ctrl+a :aclchg UserA -w "#"
UserA@host # screen -x root/watch_me