complete noob question: subdomain vs main domain

utevolux a year ago

To start, I have a mechanical engineering background with zero IT/computer science experience. I enjoy programming and would say I have an above average understanding of computers and tech, in general. I enjoy arduino projects, both building boards and programming them. I must say though that linux/servers/networks/protocols/internet and everything in between are so much more complicated than I ever imagined. I have never played with linux or servers before.

Having said that, I really wanted to get Traccar going. I managed to find a suitable VPS with Ubuntu and opted for no "control panel", so I'm doing everything through a SSH connection on Terminal (which means I google commands and copy paste them, and I am amazed at how complicated the language can be). I got everything up and running. I've closed all unused ports with CFS/LFD, I've setup a secure HTTPS connection through apache. Everything works.

My noob question is as follows: I have a domain name: call it "noob.xyz". I recently created a subdomain "total.noob.xyz". I updated DNS info on the VPS and pointed the subdomain to the VPS IP address. I updated the info in the traccar apache config file with the new subdomain. What I find odd is that my phone's Traccar Client still has "noob.xyz:5055" entered in the url field and is continuing to send data to the server without issue. I changed this to "total.noob.xyz:5055" and obviously it works, but I wasn't expecting "noob.xyz:5055" to continue working. Is there no way to "hide" the main domain and only allow the traccar client to send info on the subdomain, like I intended? Is there no way to not have a DNS entry for the main domain and only have DNS entries tied to subdomains? How do I make the main domain unreachable to the traccar client, and only let it communicate with the subdomain?

I was hoping somebody could clarify. Thanks.

Anton Tananaev a year ago

Have you removed the main domain DNS? If yes and still works, it's probably some cache.

utevolux a year ago

You were correct. It was indeed the DNS cache on my phone causing this behaviour. Thank you very much.