<![CDATA[Accessing a site - DNS flush]]>Hello. We have a site that our users cannot connect to. When they try, they get a message "Site can't be reached. dns_probe_finished_nxdomain".

The URL sites:

  • https://link.nyulangone.org/EpicCareLink/common/epic_login.asp
  • https://link.nyulangone.org/

We have cleared (flushed) the DNS cache in PFSense.

  • Status > Services > unbound

We have restarted and also stopped and started DNS Resolver.

Afterwards, the site will randomly work or not; sometimes, by itself, the portal will come up. We have tried in private windows of all browsers.

If a user is able to log in, it is only for a few minutes, and the user is kicked off.

Any troubleshoots or fixes we can try?

]]>https://forum.netgate.com/topic/177464/accessing-a-site-dns-flushRSS for NodeSun, 14 Jun 2026 03:57:05 GMTTue, 31 Jan 2023 20:53:06 GMT60<![CDATA[Reply to Accessing a site - DNS flush on Tue, 31 Jan 2023 21:13:49 GMT]]>@jlee_eye link.nyulangone.org has a 30 second TTL so any DNS problems can break/resolve every few seconds.

If you try nslookup does that work during an "outage"?

nslookup link.nyulangone.org your_pfsense_ip

Are your PCs using pfSense for DNS?

It's also very possible your browser is using DNS over HTTPS and not using pfSense for DNS at all. Many default to that nowadays.

]]>https://forum.netgate.com/post/1083405https://forum.netgate.com/post/1083405Tue, 31 Jan 2023 21:13:49 GMT