Multiple users facing DNS_PROBE_FINISHED_NXDOMAIN issue - amazon-web-services

Many of my application users started facing DNS_PROBE_FINISHED_NXDOMAIN issue intermittently. I learned that this could be possibly due to a DNS issue on users' computers or home networks, but it cannot be the case with most users.
My application is hosted on AWS and users in Norway are complaining about the application unavailability issue. When I tried connecting to multiple users, it was throwing DNS_PROBE_FINISHED_NXDOMAIN error
Surprisingly when I pinged IP from user system, it was returning response however pining domain was not working.
I also tried nslookup using domain but no response returned.
In my understanding this is not local computer issue as application works fine most of time but breaks intermittently with referred issue.
Any insight into troubleshooting the issue will be greatly appreciated.

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This type of question is super hard to answer because the possibilities are almost endless. However, from what you're saying, if some machines CAN access the server and SOME can't, the problem is related to networking, and not the server software (or Django).
Though it could be related to either if you have some weird access rules setup that you're not mentioning in your response.
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To see if it's a routing problem, do a traceroute from one of the machines that cannot access your server, and see what happens. Did the traceroute stop at a particular router on your network? Well, then that's probably an issue.
To see if it's a firewall issue, try changing the IP address of one of the machines that can't access the server to one of the machines who can. Did it work? OK, you have a firewall problem.