We have two sites, A and B. Now the phone at site A can call the phone at site B, but the phone at site B cannot call the phone at site A. When the phone at site B calls site A, the phone keeps beeping, as if the line is busy. Can you help me analyze...

I have two C3850 switches, in stacking mode. The current ISO version is 16.3.6, BUNDLE mode, and I need to upgrade to 16.6.9 version install mode. How can I do this?1. Do I need to switch from 16.3.6 BUNDLE mode to install mode and then upgrade to 16...

We have two sites, the Hub site and the Spoke site, both of which use TLOC-EXT. We found that the Spoke site Internet interface address (59.39.38.106 and 120.86.8.30) cannot be pinged from the Hub site., but the BFD sessions are normal The Internet i...