10-17-2019 02:58 AM
Hey All,
I have 9500 series Switches which is facing the firewall and plays the DNS Proxy role for clients and everything is perfect. What is the problem I want to renew license with CSSM and therefore it needs to contact tools.cisco.com. I have tested and the switch has ip connectivity to internet, ping works. But the problem is when I try to telnet tools.cisco.com 443 I see that it tries to contact IPv6 address. I tested several other domain names and all are the same with IPv6. I have disabled IPv6 unicast-routing globally, but it does not help.
telnet tools.cisco.com 443
Trying 2001:420:1201:5::A, 443 ...
% Destination unreachable; gateway or host down
Any help is appreciated.