In Packet Tracer I have 8 Cisco 2960 switches and lots of devices in my topology.
I have 5 VLANs: 11-15.
I have a 2620 Cisco router with 5 sub-interfaces: fa0/0.11-15 configured with encapsulation dot1Q and assigned to the VLANs respectively.
All devices in all VLANs can ping each other except from VLAN 12 to VLAN 13.
(Although I can ping from VLAN 12 devices to VLAN 13's subnet address and default gateway - but not the devices!!)
(VLAN 13 devices are printers so they can't ping back - or I don't know how).
How do I troubleshoot this issue please?