Useful netowork command and tools

ipconfig /displaydns
w/o real dns for local development: any.localdev.us.
nslookup any.localdev.us

nslookup
> set type=NS/MX/CNAME/AAAA (Ipv6 A-Record lookup)
pathping tracert microsoft.com

https://www.whatismyip.com/  NAT rout to different PC by port

telnet cnn.com 80
netstat -ano
nslookup set type=mx  telnet ..._smtp..gmail 25
nmap -v cnn.com port scan open source

WireShark, Fiddler
lsof -i TCP
sudo lsof -i |grep tftp
wget cnn.com

telnet localhost 107  ^] =exit (as tcp client)
pgrep -a my_tcp_sever  pgrep my_tcp_server | xargs kill