Friday, June 12, 2020

Cannot bring up certain TLS/SSL pages

Totally stumped. This network was inherited.

Site has a Cisco 1941 with DIA and a cellular card. IPSec tunnels are formed on each interface to the datacenter, 4 tunnels total. OSPF is running for L3 routing between site and datacenter.

Internet access is in datacenter. It goes thru a pair of 5525x running 9.8 and using Cisco WSA via WCCP for SSL inspection, monitoring and filtering.

On 6/7, the WSA config was removed from the ASA. The appliances were shut down a few days later. At this one specific site, I CANNOT get some HTTPS sites to work. The cursor spins and eventually times out. When I take the router out of the mix, all is good. This isn't all https, just select. On the router we are NOT running WCCP, WAAS, or anything else. I've tried setting up new service on the router with no luck. When a computer is connected to the same modem, no problem. DNS resolves perfectly. I cannot figure out why we cannot pull up pages. From wireshark, we see the 3way shake happen, then the server sends a key exchange and the client no longer responds. Then the server closes the connection.

There was a dhcp option configured for wpad, but that was removed at the beginning of troubleshooting. This is the only site affected. We made specific access rules for our test subject, even changed its NAT, all to the same result.

Any remote idea what this could be?

Trent



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