I have a issue in my network. In terms of OSI I am OK in the physical layer. My link is OK because I tested connecting a computer on a fiber link, and I was able to surf the Internet, but when I make a connection between two Cisco switches, I just have CDP - there is no propagation of VLANs.
There is something even stranger. I have a successful ping in a way. Example: I have a Switches A and B connected through that link. I can ping from B to A and get an answer, but ping doesn't work if I ping from A to B.
It seems very weird to me. I believe it is a VLAN problem, but I do not understand because I can't successfully ping both ways.
I verified that I have the same configurations on both switch ports. I have
switchport mode trunk and the native VLAN is 1. I think that the problem is because of a broadcast storm, but I do not know how to verify that. The other situation that I have in my network is this is a multivendor network. My "core" switch is a 3Com. I have Cisco switches, HP switches and TP-Link switches with RSTP.
Should I have a same version of STP in all switches? Could it be a physical problem? Could I have problems with the fiber link? In the moment when the fail occurred, a person was working near to the rack where the fiber ends. I have two transceivers, and I always test between gigabit ethernet ports.