How to check if port 123 is ready for time sync?

Question

I am going to do a time sync for my server.

Tried portqry to the time server with below results:

C:\PortQryV2>portqry -n "time server" -e 123 -p both

Querying target system called:

"time server"

Attempting to resolve IP address to a name...

Failed to resolve IP address to name

querying...

TCP port 123 (unknown service): NOT LISTENING

UDP port 123 (ntp service): LISTENING or FILTERED

UDP port 123 (ntp service): LISTENING or FILTERED

I am not sure if the port is available for time sync or not. But our team has confirmed that no firewall should be blocking that.

It is not showing "LISTENING" because it is a UDP port?

Answer 1

LISTENING or FILTERED simply means Portqry does not get a response from the port specified. The problem should be at

Failed to resolve IP address to name

resolve the hostname and try again.

Answer 2

I tried on a PC which is not going to do the time syn. It can resolve the hostname but got the same result for UDP query:

C:\PortQryV2>portqry -n "IP Address" -e 123 -p both

Querying target system called:

"IP Address"

Attempting to resolve IP address to a name...

IP address resolved to xxx.corp.com

querying...

TCP port 123 (unknown service): NOT LISTENING

UDP port 123 (ntp service): LISTENING or FILTERED