On 8/5/10 8:13 AM, David Burgess wrote: > Paul, > > I understand your post up to this point: > >> if the switch's port are set so that connected devices can't cause them >> to flip from untagged to tagged mode (in cisco speak from access to >> trunk - "switchport nonegotiate" > > I'm looking at the help file for my switch, and thinking this section > is saying what you're saying: > > "Ingress Filtering - When enabled, the frame is discarded if this port > is not a member of the VLAN with which this frame is associated. In a > tagged frame, the VLAN is identified by the VLAN ID in the tag. In an > untagged frame, the VLAN is the Port VLAN ID specified for the port > that received this frame. When disabled, all frames are forwarded in > accordance with the 802.1Q VLAN bridge specification. The factory > default is disabled."
The "switchport nonegotiate" command has a different meaning in the context of Cisco Catalyst switches: It disables the use of Dynamic Trunking Protocol, a proprietary means of determining whether two switches will use trunking (tagged frames) to carry traffic between them. There may be exceptions, but DTP generally won't work between a Cisco and a non-Cisco device, or between two non-Cisco devices. Here's an sample reference from the Catlyst 3560 docs: http://is.gd/e4mFq dn --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected] Commercial support available - https://portal.pfsense.org
