3Com SUPERSTACK 3 3226 Release Notes

12 SUPERSTACK
®
3 SWITCH 3226 AND SWITCH 3250 SOFTWARE VERSION 1.02 RELEASE NOTES
default gateway setting to be lost. You should
always check the IP address and route
configuration when restoring the configuration on
another unit.
IGMP
Disabling IGMP when there are hosts subscribing to
multicast IP streams may prevent clients from
subscribing to multicast IP groups. Hosts may be
unable to re-subscribe to the same multicast IP group,
for more than 5 minutes, or until the unit is
re-booted.
Spanning Tree
■ When connecting switches together, 3Com
recommends that spanning tree fast start should
be disabled on the interconnecting ports (it is
enabled by default on all 10/100 ports and
disabled by default on 10/100/1000 and SFP
ports). This can be done using the Physical
Interface > Ethernet > Setup command on the
Web interface.
■ When connecting switches together, if spanning
tree fast start is not disabled on the
interconnecting ports, any previously learned
addresses on links that become blocked will not
correctly age out until the aging time has passed. If
the switch is power cycled then the device will
learn the addresses correctly.
■ You must enable spanning tree before making
changes to spanning tree settings. If you try to
change spanning tree settings while the protocol is
disabled the following error messages will be
generated:
Failed to set forward-time
Failed to set hello-time
■ When you enable spanning tree, all spanning tree
settings are reset to their default values. If you
want to use custom settings for spanning tree, you
must configure spanning tree after enabling it.
Roving Analysis Port
■ When the roving analysis port feature is activated
the analyzer should see a copy of all packets sent
and received by the mirror port. The switch does
not currently mirror frames sent by the
management CPU of the switch itself. The analyzer
port will therefore be unable to show
management traffic from the unit or protocol
control packets such as RIP which are being sent
out of the mirror port.
■ While the analyzer port is active it still operates as
a normal network port, allowing traffic to be
switched to and from other network ports. You
must be careful to differentiate traffic seen by the
analyzer which is from the mirror port and other
network traffic which may be being sent through
the analyzer port.
■ The traffic sent out of the analyzer port follows the
VLAN membership setup for the analyzer port and
not the mirror port. You must manually
reconfigure the VLAN membership of the analyzer
port to match the mirror port or you will not see
the correct tagged / untagged packets on the
analyzer.

3Com SUPERSTACK 3 3226 Specifications