User guide

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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 necessary to have
an IP address associated with a VLAN if you intend to manage (Telnet, SNMP, ping)
through that VLAN or route IP traffic. You can also configure multiple default routes
for the system. The system first tries the default route with the lowest cost metric.
STP
You have connected an endstation directly to the switch and the endstation fails to
boot correctly:
The switch has STP enabled, and the endstation is booting before the STP initialization
process is complete. Specify that STP has been disabled for that VLAN, or turn off STP
for the switch ports of the endstation and devices to which it is attempting to connect,
and then reboot the endstation.
The switch keeps aging out endstation entries in the switch Forwarding Database
(FDB):
Reduce the number of topology changes by disabling STP on those systems that do not
use redundant paths.
Specify that the endstation entries are static or permanent.