Connect to guest console

Description

This option will allow you to connect to the guests consoles.

Notes:

• "telnet" package must be installed
• The session will be recorded in a log file:
  • If 'set OPA0 log=' is found in the configuration file (not available with all CHARON products versions), the log will be stored in the temporary folder: '/tmp/console.<configuration file name shortened>.tmp.log' and will be overwritten for each session. It is just kept for information as the console log is managed by the CHARON emulator itself.
  • If there is no 'set OPA0 log=' line in the configuration file, the file will be located in '/opt/charon/log/console.<configuration file name shortened>.log'
• If 'stop_on' and/or 'break_on' features are enabled in the configuration file, this will be reminded before starting the telnet session

• To leave the telnet session, press the escape character which is by default CTRL + ] . This character can be changed in the /root/.telnetrc file by defining the 'set escape' parameter:
  Example:

  # cat /root/.telnetrc DEFAULT   mode char   set escape ² #

  Pressing the escape key will lead you to the 'telnet> ' prompt. To leave the session, enter 'quit'

• If a connection to the console is active from the server, you will be prompted to kill the previous one.
• If a connection to the console is active from anothe location, it will be displayed but will not be killed. This will have to be done manually.
• Emulator termination check:
  
  • For CHARON-AXP, if the 'power off' command is detected (or shortened command), the guest STOP state will be set to REQUESTED
  • If the emulator is no more running when you leave the session, you will have to confirm that is requested or not
• The console port number is displayed per guest. If a port number is used more than once, an alert will be displayed

Autoconnect feature

This feature has been implemented to prevent from buffer issues with old CHARON-AXP versions where a connection to the console had to be active for the guest not to be blocked (hang). This could prevent from booting the system.

Advantage of this feature is it will record console output for CHARON products versions that have not the console log feature implemented and activated: every 1 minute, a crontab job (/opt/charon/utils/charon_console_autoconnect) will check if a connection to the console is active or not. If not, a telnet session will be engaged in the background.

This feature can also be disabled from this menu and is automatically disabled for the guest that have console log recording with the 'set OPA0 log=' option.

Example

Connect to guest console main screen

We can see above:

• the console is already locked by the autoconnect utility for the "mvax4106" virtual machine because:
  • the autoconnect feature is enabled and
  • the configuration file does not contain any specification to the console log (no "set OPA0 log = ..." line)
• the console is free for "myds20" virtual machine because:
  • the configuration file contains a specification to the console log: "set OPA0 log = /consolelogs" ( which corresponds to a folder )
  • no one is connected to the console

Connection to a virtual machine without console log defined in the configuration file

We will now connect to the "mvax4106" virtual machine console and kill the active session:

We can see above the F6 key is enabled in the configuration file and the telnet escape character has not been customized (set to default CTRL + ]). We see also the session is recorded to the "/opt/charon/log/console.mvax4106.log" file (append mode).

Connection to a virtual machine with console log defined in the configuration file

Connection to the "myds20" virtual machine console:

We can see above, compared to the "mvax4106" console connection performed previously, the session is recorded to the "/tmp/console/myds20.tmp.log" file (overwrite mode), valid then only for this session because it will also be recorded by the emulator itself within the "/consolelogs" folder.