We have two cisco 4500 series switches in connected in HSRP mode with multiple trunk ports. The STP is PVST.
Currently the ISP has provided a single internet link from their switch -1 its now connected to our 4500 switch-1.
For redunt purpose in ISP end, the ISP has added switch-2 and given the Link-2 for us.
if i connect to Link-2 in 4500 switch-2 in my end it may form a loop. How to avoid any loop as the ISP end configurations is not in my control.