Check TCP/UDP port connectivity from ESXi host

Run below command from esxi shell:

For TCP Port:

nc -vz x.x.x.x/name Port

example: if you want to check connectivity from esxi to 10.10.10.10 and TCP port (8000).

nc -vz  10.10.10.10 8000

Connection to 10.10.10.10 8000 port [tcp/*] succeeded!

For UDP Port:

nc -vz -u x.x.x.x/name Port

example: if you want to check connectivity from esxi to Syslog server (10.10.10.10) and UDP port (514).

nc -vz -u 10.10.10.10 514

Connection to 10.10.10.10 514 port [udp/*] succeeded!