1

I own two domain names (cyklussoftware.com and totalstudent.io). They are both registered through and managed by GoDaddy. Both of them have an @ and a * in their DNS A records. Both the @ and the * for both domains point to the same IP address.

Last night I was tinkering with an Nginx reverse proxy and Docker containers for an Angular app and a ASP.NET Core web API. All of a sudden I could no longer connect to api.totalstudent.io. I thought this was an Nginx configuration issue, but I can't ping api.totalstudent.io or perform a traceroute. Neither can resolve the location of api.totalstudent.io.

I used https://www.whatsmydns.net to take a look at DNS propagation and api.totalstudent.io is nowhere to be found. What's odd is that every other sub domain that I tested for either cyklussoftware.com or totalstudent.io resolves just fine. The "api" sub domain for totalstudent.io is the only broken one. The "api" sub domain for cyklussoftware.com resolves fine.

So, asdf.totalstudent.io resolves. asdfasdfasdf.totalstudent.io resolves. asdf.ap.totalstudent.io resolves. asdf.api.totalstudent.io does NOT resolve.

It's worth mentioning that I used Let's Encrypt Certbot to request a SSL certificate for *.api.totalstudent.io using the script found here: https://github.com/alambrec/validation-hooks-certbot-godaddy. I've successfully used this script to request root and wildcard certificates before, so I'm not sure why it would have broken something now. Plus the ssl certificate and the api sub domain were working fine for a while.

Has anyone encountered something like this before?

Note: I was considering posting this on the Network Engineers site instead. Please let me know if I need to move it.

Schmidty15
  • 11
  • 1
  • What did you see in your GoDaddy DNS records? – Michael Hampton Dec 10 '18 at 23:34
  • @MichaelHampton these are the records that I see: 2x A, 2x CNAME, 2x NS, 1x SOA, 2x TXT. My name servers are set to Default. – Schmidty15 Dec 10 '18 at 23:36
  • I will mention that the "Nameservers" section lists two different entries than the NS records. I'm not sure if they should be the same or if it doesn't matter. When I did my initial configuration last month or so, I only changed the "Nameservers" section. I can't recall if the NS records used to be the same as the Nameservers or not. – Schmidty15 Dec 10 '18 at 23:40
  • I set the Nameservers section to Default again and now they're the same as the NS records. I guess I'll see if anything changes. Still odd though given that I didn't touch the Nameservers entry yesterday. Also odd that they didn't update in the first place when I did change the Nameservers last month. – Schmidty15 Dec 10 '18 at 23:46
  • it should work as expected. In theory some subdomain may be cached so in case you have tried it already and then add the wildcard the cached value may be still in place.... Please note that that wildcard will cover only not defined records and it will cover just one level so *.totalstudent.io will not cover *.api.totalstudent.io. – Kamil J Dec 11 '18 at 12:29

0 Answers0