3Com SuperStack 4 Configuration Manual page 425

Recovering your XRN
Network
Unit Failure
Interconnect Failure
How XRN Interacts
with other 3Com
Switches
3 Connect up your ports. As LACP was enabled in
now automatically configure themselves.
4 Configure the router IP interfaces.
5 Ensure that RSTP is enabled across the network.
Legacy aggregated links are not resilient to an interconnect failure. Hence the
3Com recommendation to use IEEE 802.3ad aggregated links (LACP) for maximum
resilience.
If an automatic aggregated link (created by LACP) contains ports with different
VLAN membership, the aggregated link will inherit the VLAN memberhip of the
first port that comes up in the aggregated link. It will override any pre-defined
VLAN membership for the aggregated link.
In the event of a failure within your XRN network, 3Com recommends that you
follow the recommendations below.
The steps below outline the procedure to recover your XRN network in the event
of a unit failure within your Distributed Fabric.
1 Obtain a Switch and ensure it is installed with the same software version as the
failed Switch.
2 Initialise the new Switch so it is operating with its factory default settings.
3 Connect the new Switch to the operational Switch to form the Distributed Fabric.
4 IP interfaces and VLANs will be converged between the Switches, that is, IP
interfaces and the creation of the VLANs is done automatically on the new Switch.
However, any port-based configuration must be done manually.
5 If any Switch features, for example, IGMP snooping or passwords are not set to
default state then these should be reset after the new Distributed Fabric has been
formed.
The steps below outline the procedure to recover your XRN network in the event
of an interconnect failure within your Distributed Fabric.
1 Obtain a new cable.
2 Install the new cable.
This section provides guidelines on connecting legacy and new 3Com Switches
(including non-XRN enabled Switches) to an XRN Distributed Fabric.
the features supported by the Switches that can be used when connecting to a
Distributed Fabric.
For detailed information on how the Switch features interact with XRN , refer to
the following section
Table 466 Features supported by 3Com Switches connecting to an XRN Distributed Fabric
3Com Switch
SuperStack II Switch
1100 Family
"How XRN Interacts with other Features"
Resilient STP/
Links RSTP
Yes Yes
Recovering your XRN Network
step 1 the aggregated links will
on page
Manual Link
MSTP Aggregations
No Yes
437
Table 466 lists
438.
LACP Link
Aggregations
No