Lost connection to internet websites yet could ping urls.

Hi Simon and welcome to the UTM Community!

There are just too many questions we'd need to ask you first.

Please compare your configuration to DNS best practice and Configuring HTTP/S proxy access with AD SSO.

Cheers - Bob

good evening

I had exactly the same problem (web page could not be displayed)...

I and Sophos Support checked everything that could be verified.

Only solution for me was a factory default settings.

Hi Bob,

Thanks for your response.

I have checked through your best practice and there are quite a few differences in our DNS settings.  We have "Extenal Network" on the "allowed networks" for DNS.  We also have 2 IPs given by our ISP rather than Google's one.  Is it better to change this to Google's DNS?  In request routing the domain is written as yourdomain.loc instead of "20.16.172.in-addr.arpa" as suggested, however the UTM still lists machine names in logs not IPs.  Our internal DNS server point to 2 NHS IP addresses first then the UTM.  This was changed due to problems we had sending emails to NHS addresses.

The SSO is set up as specified in your article and works as described.  However when the proxy setting is turned on in IE I cannot connect to the UTM webadmin.  (I have "bypass proxy for local addresses" checked and it works for all other internal sites.)

Do you think my DNS settings may have been a potential cause?  The issue has not occurred since so there will not be any way to test if any changes work unless it happens again.

Great, thoughtful response, Simon.  You would want entries for both yourdomain.loc and 20.16.172.in-addr.arpa in Request Routing, so I don't understand how Reporting shows machine names instead of IPs.  You probably don't get any benefit from having "External (Network)" in 'Allowed Networks' for DNS.  Some ISPs hijack DNS, thus interfering with the SMTP Proxy's use of RBLs - if you're not using Mail Protection or your ISP is not hijacking DNS, the use of Google or other is less important.  However, I wonder if the issue isn't indeed with using NHS' DNS servers.

Yes, skipping the Proxy to access WebAdmin is usual.

Cheers - Bob

Thanks for your help Bob, I will add the extra entry in Request Routing and remove "External (Network)" from the DNS allowed networks.

We do use mail protection on this UTM so perhaps I should change the DNS forwarder to Google.  We do often find incoming mail can be delayed up to 20 minutes although I think this is more likely to be due to the NHS DNS servers being the primary forwarders on our internal DNS server.  I need to have a play around with these out of hours.

The connection problem may have been a one off, but if it does happen again I will try moving the UTM to the top of the DNS forwarders list in our internal DNS server to see if that helps.

Thanks again!