change default port of vm knot #315

port 6000 is one of restricted ports, leading to ERR_UNSAFE_PORT when opened on browser. In this case, port 6000 is preserved for X11.

It would be better if we change it to something else like 6400.

source:

• https://fetch.spec.whatwg.org/#port-blocking
• https://chromium.googlesource.com/chromium/src/+/main/net/base/port_util.cc#107