When connecting a Force10 switch running PVST to a Cisco switch the Force10 blocks the untagged VLAN or puts the port into errdisable state. Force10 switches do not allow PVST+ BPDU (tagged or untagged) on an untagged port. If this occurs the switch places the port into an err-disable state or blocks the untagged VLAN. This could possibly cause the network not to converge.
To prevent this action on the switch you can use the no spanning-tree pvst err-disable cause invalid-pvst-bpdu command from the interface specific configuration mode. After this entry if the port receives a PVST+ BPDU on the untagged VLAN the BPDU is dropped and the port remains operational.
Article ID: SLN248779
Last Date Modified: 03/30/2017 02:42 PM