telnet

shark@ubuntu:~$ telnet 192.168.2.15 23
Trying 192.168.2.15...
Connected to 192.168.2.15.
Escape character is '^]'.

Welcome to the Mer/SailfishOS Boat loader debug init system.

Log so far is in /init.log

To make post-switch_root halt before starting systemd, perform:
  touch /target/init_enter_debug2
(When run post-switch_root, telnet is on port 2323, not 23)

You may inject commands into init shell process (PID 1):

To see output of commands as they're injected:
  tail -f /init.log &
To run a command:
  echo "ls -l /" >/init-ctl/stdin

(Be careful if you experiment with exec as you need to terminate
daemons and disable busybox hotplug handling)

To allow init to continue:
  echo "continue" >/init-ctl/stdin

In order to work safely with the device's mmc you should
  echo "umount_stowaways" >/init-ctl/stdin

Then you can mount and modify exported mass storage on host. When done
  echo "mount_stowaways" >/init-ctl/stdin


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