check remote connection is open or not

I have a centos linux , and installed sql server

I can use telnet localhost 3306 to connect the port , but use telnet IP 3306 is not work , just wonder if the 3306 port is only allow for localhost to connect , not allow remote connection , maybe if is blocked by server firewall , I am not sure .

would advise how can I check if this port allow connect from remote or not ?

thanks