DNS record look up with Python / Django [dnspython]

Question

I am trying to get DNS records of particular domain. So, I found dnspython package where it could be easily done. It works fine when I run it from my computer. However, when I call it from Django views it shows the previous records (old records) which means it's not updating.

Is it some kind of caching in OS level? Note that, I am also using Docker. Restarting docker and clearing cache in Django didn't help, still shows old records.

Here's the sample code for checking records:

import dns.resolver
result = dns.resolver.resolve("domain.com", "TXT")[0].to_text()

The code snippet above works and shows any update in TXT record, when I run it from my computer. However, in Django it's stuck in old records and not updating.

In Django views:

def verify_dns_view(request, domain_id):
    domain = get_object_or_404(models.Domain, id=domain_id)
    mx_record = dns.resolver.resolve(domain.name, "MX")[0].to_text()
    txt_record_spf = dns.resolver.resolve(domain.name, "TXT")[0].to_text()
    ...
  

Answer 1

There always might be a different DNS server that your app and PC are connecting to. In your case app server is "further away" from the server where the actual domain is registered so it did not update the record yet.