>From what I understand LLDP don't support the 4-byte tag field in an Ethernet >frame. It should be expecting the EtherType of 0x88cc instead.
Doug -----Original Message----- From: juniper-nsp-boun...@puck.nether.net [mailto:juniper-nsp-boun...@puck.nether.net] On Behalf Of Dale Shaw Sent: Sunday, February 06, 2011 12:07 AM To: juniper-nsp Subject: [j-nsp] LLDP-MED support on EX-series - dot1q trunks Hi all, I'm a bit confused about LLDP-MED on dot1q trunks. We have cases where we need to support interfaces connecting to PCs via an IP phone (typical setup) however the PC is running VMware Player and the 'guest' operating system's frames are tagged in order to differentiate them from the host's (it's a software developer image). We usually use LLDP-MED on access ports when it's just the phone (tagged) + PC (untagged), and that works well. Aside from configuring the developer ports as trunks, I'm not aware of a way to support 2 x tagged + 1 x untagged. I've observed that LLDP-MED network policy TLVs are not transmitted on interfaces configured as trunks. Without having a mad scientist-level understanding of LLDP-MED, I'm unsure if this is due to lack of support in the protocol itself, a limitation on EX-series specifically, or what. Couldn't find the answer in any J or C documentation. Basic LLDP functionality continues to work fine - we still see the phones as adjacent - but we need to instruct the phone on which VLAN ID to use via another mechanism (DHCP in this case). We're running RSTP and limit the VLANs permitted on such interfaces but it's still not as elegant as the access+LLDP-MED method. Cheers, Dale _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp