The Haskell Network Stack.
NOTE: This example is out of date
You first need to set up a bridge device, br0; the echo servers are
configured to use this bridge in Xen. The configuration files are
udp-test/udp-test.config and tcp-test/tcp-test.config.
Assuming you are working in a Cabal sandbox at the top-level of the
repo, and have done halvm-cabal install hans, you can run the TCP
and UDP echo server examples with
sudo xl create -c ../udp-test/udp-test.config
and
sudo xl create -c ../tcpp-test/tcpp-test.config
where -c makes them print their log messages to standard out. They
are configured to use DHCP and will log the IP address they receive
after start up; they listen on port 9001.
You can then test them with NetCat, using
nc -u <ip addr> 9001
for UDP and
nc <ip addr> 9001
for TCP. Whatever you enter will be echoed back.