Using the screen
command#
The screen command is available to execute long-running commands (for example, when upgrading) in the background.
The following commands require the running of screen:
cluster provision
cluster upgrade
app template
voss export type <args>
voss export group <args>
voss subscriber_data_export
A message is displayed to indicate that screen should be run first:
This is a potentially long-running command and should be executed in a screen session
Run `screen` and then execute the command again
The use of screen is not affected by the use of the --force
parameter with
any of these commands.
The commands then run in a screen session that can be reconnected. The standard screen command parameters are available, in particular:
screen - start a new session
screen -ls - show sessions already available
screen -r [screen PID] - reconnect to a disconnected session
The version of screen used in VOSS Automate also supports the creation of a log file. If long-running commands will be run, the log file captures screen console output up to the session timeout. A message shows:
timed out waiting for input: auto-logout
To create a screen log file:
Run screen and wait for screen to open.
Press <Ctrl>-a then : (colon). This will enter screen command mode at the bottom of the console.
Create your screen logfile in the
media/
directory:In screen command mode, type logfile media/<screen-logfilename>.log
Press <Enter>
Press <Ctrl>-a and then H to start writing to the log file
Run your commands.
If the screen session times out, you can obtain console output from the log file, for example:
$ sftp platform@<host>:media/<screen-logfilename>.log