gRPC
Check server connection
Use nc in macOS.
$ nc -vz 192.168.1.2 8087
found 0 associations
found 1 connections:
1: flags=82<CONNECTED,PREFERRED>
outif utun1
src 192.168.1.100 port 51249
dst 192.168.1.2 port 50051
rank info not available
TCP aux info available
Connection to 192.168.1.2 port 50051 [tcp/*] succeeded!
Or brew install telnet first, then
$ telnet 192.168.1.2 50051
Trying 192.168.1.2...
Connected to 192.168.1.2
Escape character is '^]'.
@^]
telnet> quit
Connection closed.