topic Re: URL Filtering Error in Next-Generation Firewall Discussions

URL Filtering Error

Sanjay_Ramaiah — Thu, 02 Feb 2023 15:12:48 GMT

Hi All,

We are getting an error as "Hmmm... can't reach this page" site's server ip could not found.

And other page is also getting the same error.

Is this a known error? I can see the logs with the IP resolved so i dont think this should be DNS issue as well.

May i know what could be the best way to fix this issue?

Regards,

Sanjay S

Re: URL Filtering Error

Adrian_Jensen — Thu, 02 Feb 2023 16:03:43 GMT

"xxx server ip could not be found" or ERR_NAME_NOT_RESOLVED is a DNS lookup problem. The browser couldn't find the IP for the FQDN in the URL. Or the content of the page is an iframe of a different URL with an invalid DNS.

Try copying the FQDN out of the URL and doing a DNS lookup in a command prompt.

Re: URL Filtering Error

Sanjay_Ramaiah — Fri, 03 Feb 2023 08:02:54 GMT

Hi Adrian,

One URL looks to be resolving when we do nslookup and the other is not resolving.

But both prompting the same error. Though we have allowed the url as "*.url.com/" the issue persists. And it is not hitting the rule we implemented. It is being by passed and hitting other after the allow rule. Not really sure what i am missing or how to check. As this error seems to be more likely to do with local system itself.

Any thoughts on this?

Regards,

Sanjay S

Re: URL Filtering Error

murali438 — Fri, 03 Feb 2023 10:43:27 GMT

Hello Sanjay,

How are the logs looking on your PA.

Re: URL Filtering Error

Adrian_Jensen — Fri, 03 Feb 2023 15:40:08 GMT

Try loading the developer tools in Chrome, then going to the URL. Look at the network tab in the developer tools and see what it errors on.

Re: URL Filtering Error

Sanjay_Ramaiah — Mon, 06 Feb 2023 10:37:41 GMT

Thank you Adrian,

I see the URL is re-directing to other URL and that URL is showing (Failed) status and the Type is document in the Developer Tools Network Tab.

We are decrypting the URL, So if i dont decrypt the URL will it work? Any suggestions please?

Regards,

Sanjay S

Re: URL Filtering Error

Adrian_Jensen — Mon, 06 Feb 2023 19:24:36 GMT

If it is a decryption error then in the logs it will most likely show "Session End Reason: decrypt-error" in the logs. You can try bypassing decryption and see if that fixes it, though I suspect it won't.

Note that you can not bypass decryption on a particular URL, you have to bypass the entire server (either by IP or by FQDN). This is because you can't know the URL without decryption the session, just the server name the client is connecting to.