Screen Commands and persistent connections 🐧
Screen Commands to create windows
🐧 Inspect out /root/.screenrc file
🐧 Start screen
🐧 Create multiple screen windows, rename them, and move between them
💬 Let's learn all about Screen! 🐧🐧🐧
1. Verify your /root/.screenrc file
Example Output
controlplane $ cat /root/.screenrc
# GNU Screen - main configuration file
# # All other .screenrc files will source this file to inherit settings.
# # Author: Christian Wills - cwills.sys@gmail.com
#
# # Allow bold colors - necessary for some reason
attrcolor b ".I"
#
# # Tell screen how to set colors. AB = background, AF=foreground
termcapinfo xterm 'Co#256:AB=\E[48;5;%dm:AF=\E[38;5;%dm'
#
# # Enables use of shift-PgUp and shift-PgDn
termcapinfo xterm|xterms|xs|rxvt ti@:te@
#
# # Erase background with current bg color
defbce "on"
#
# # Enable 256 color term
term xterm-256color
#
# # Cache 30000 lines for scroll back
defscrollback 30000
#
# # New mail notification
# backtick 101 30 15 $HOME/bin/mailstatus.sh
#
hardstatus alwayslastline
# # Very nice tabbed colored hardstatus line
hardstatus string '%{= Kd} %{= Kd}%-w%{= Kr}[%{= KW}%n %t%{= Kr}]%{= Kd}%+w %-= %{KG} %H
%{KW}|%{KY}%101`%{KW}|%D %M %d %Y%{= Kc} %C%A%{-}'
#
# # change command character from ctrl-a to ctrl-b (emacs users may want this)
#escape ^Bb
#
# # Hide hardstatus: ctrl-a f
bind f eval "hardstatus ignore"
# # Show hardstatus: ctrl-a F
bind F eval "hardstatus alwayslastline"
2. Create a screen session
Example Output
GNU Screen version 4.08.00 (GNU) 05-Feb-20
Copyright (c) 2018-2020 Alexander Naumov, Amadeusz Slawinski
Copyright (c) 2015-2017 Juergen Weigert, Alexander Naumov, Amadeusz Slawinski
Copyright (c) 2010-2014 Juergen Weigert, Sadrul Habib Chowdhury
Copyright (c) 2008-2009 Juergen Weigert, Michael Schroeder, Micah Cowan, Sadrul Habib Chowdhury
Copyright (c) 1993-2007 Juergen Weigert, Michael Schroeder
Copyright (c) 1987 Oliver Laumann
This program is free software; you can redistribute it and/or modify it under the terms of the GNU
General Public License as published by the Free Software Foundation; either version 3, or (at your
option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License along with this program (see the
file COPYING); if not, see https://www.gnu.org/licenses/, or contact Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301 USA.
Send bugreports, fixes, enhancements, t-shirts, money, beer & pizza to screen-devel@gnu.org
Capabilities:
+copy +remote-detach +power-detach +multi-attach +multi-user +font +color-256 +utf8 +rxvt
+builtin-telnet
[Press Space or Return to end.]
3. Verify that you are attached in screen
Example Output
controlplane $ screen -ls
There is a screen on:
111343.pts-0.controlplane (04/24/23 10:10:46) (Attached)
1 Socket in /run/screen/S-root.
4. Split the screen horizontally
5. Jump between the horizontal screen sessions
6. Rename the window you're in "Window1"
7. Create a new window and name it "Window2"
Screen Commands for logging sessions
🐧 Detach from screen session and verify it is still there
🐧 Reconnect and then kill the session
🐧 Create a new screen session with logging enabled to
/root/screenlog.log
8. Detach from screen session
9. Verify that screen session is still running
Example Output
controlplane $ screen -ls
There is a screen on:
111343.pts-0.controlplane (04/24/23 10:10:46) (Detached)
1 Socket in /run/screen/S-root.
10. Reconnect to that session
11. Kill each window sessions
12. Create a screen session with logging enabled to /root/screenlog.log
13. Execute a command to log it out
Example Output
controlplane $ for i in $(seq 100); do uptime; sleep 1; done
10:33:07 up 3:08, 1 user, load average: 0.35, 0.37, 0.44
10:33:08 up 3:08, 1 user, load average: 0.35, 0.37, 0.44
10:33:09 up 3:08, 1 user, load average: 0.35, 0.37, 0.44
10:33:10 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:11 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:12 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:13 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:14 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:15 up 3:08, 1 user, load average: 0.53, 0.41, 0.45
10:33:16 up 3:08, 1 user, load average: 0.53, 0.41, 0.45
10:33:17 up 3:08, 1 user, load average: 0.53, 0.41, 0.45
14. Detach the screen
15. Check log file
Example Output
controlplane $ cat /root/screenlog.log
controlplane $ for i in $(seq 100); do uptime; sleep 1; done
10:33:07 up 3:08, 1 user, load average: 0.35, 0.37, 0.44
10:33:08 up 3:08, 1 user, load average: 0.35, 0.37, 0.44
10:33:09 up 3:08, 1 user, load average: 0.35, 0.37, 0.44
10:33:10 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:11 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:12 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:13 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:14 up 3:08, 1 user, load average: 0.32, 0.37, 0.44
10:33:15 up 3:08, 1 user, load average: 0.53, 0.41, 0.45
10:33:16 up 3:08, 1 user, load average: 0.53, 0.41, 0.45
10:33:17 up 3:08, 1 user, load average: 0.53, 0.41, 0.45
^C
Look at you, learning Linux 🐧! You used Screen to run different sessions!
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