I was setting up OKD on a separate VLAN and wanted to used the OKD DNS service but it just wasn’t working and I felt it was a connectivity/firewall issue but could not find a tool to test.

I was testing on my Windows 10 desktop connecting to a Fedora DNS server.

Port Query

I have found and used Port Query UI, PortQryUI, from Microsoft:

https://www.microsoft.com/en-us/download/details.aspx?id=24009

DNS works on TCP and/or UDP port 53 so this is what I tested. This tool does not test DNS works, it tests network connectivity. For me, while the problem was happening, I got back:

This lead me to believe it was a firewall issue on the box and after opening up the TCP port it then worked and the query returned: