3Com 9100 Vlan names, 802.1Q links do not work correctly, VLANs, IP Addresses and default routes

154APPENDIX C: TROUBLESHOOTING

which should now allow you to re-enter the previous command without error as follows:

localhost:26 # config vlan red add port 1,2

VLAN names:

There are restrictions on VLAN names. They cannot contain whitespaces and cannot start with a numeric value unless you use quotation marks around the name. If a name contains whitespaces, starts with a numeric, or contains non-alphabetical characters, you must use quotation marks whenever referring to the VLAN name.

802.1Q links do not work correctly:

Remember that VLAN names are only locally significant through the command-line interface. For two switches to communicate across a 802.1Q link, the VLAN ID for the VLAN on one switch should have a corresponding VLAN ID for the VLAN on the other switch.

If you are connecting to a third-party device and have checked that the VLAN IDs are the same, the Ethertype field used to identify packets as 802.1Q packets may differ between the devices. The default value used by the switch is 8100. If the third-party device differs from this and cannot be changed, you may change the 802.1Q Ethertype used by the switch with the following command:

config dot1p ethertype <ethertype>

Changing this parameter changes how the system recognizes all tagged frames received, as well as the value it inserts in all tagged frames it transmits.

VLANs, IP Addresses and default routes:

The system can have an IP address for each configured VLAN. It is only necessary to have an IP address associated with a VLAN if you intend to manage (Telnet, SNMP, ping) through that VLAN. You can also configure a default gateway.