tcpconsole is an network emergency console for Linux (as it uses lowlevel Linux specific systemcalls). When your system no longer responds to ssh/telnet logins, you can still connect to tcpconsole (using standard telnet) and get a screendump of the physical console, the process-list, do 'sysrq'-calls (for system debugging and crash recovery) and list the contents of the Linux kernel message buffer (dmesg). The program does not do any fork()ing and as little as possible other resource-allocation.
Please note that this is intended to be used on a management-lan as the password is transmitted in clear-text accross the network (as using SSL would require all kinds of resources).
It uses the following techniques to become as much available as possible:
0.7 resource leak fixes, sigkill instead of sigterm, auto disconnect for hanging sessions
0.6 systemd compatible
0.4 infinite loop fix
0.3 initialization of logging fix
0.2 added functionality to kill one or more processes
0.1 initial release