Installation guide

Switch Services
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• Do not allow different port speed/duplex settings on members. Each members should have the
settings.
• In a redundancy group of three switches (S1, S2 and S3), if S1 has X licenses, S2 has Y licenses and
S3 has Z licenses, the license count is X+Y+Z (the aggregation of each switch).
• A cluster license is re-calculated whenever a new switch brings existing licenses to a group or an
existing switch’s license value changes (increases or decreases).
• A simple switch reboot will not initiate a new cluster license calculation, provided the re-booted
switch does not come up with different installed license.
• A change to an installed license during runtime initiates a cluster license calculation.
• If an existing redundancy group member goes down, it will not initiate a cluster license calculation.
• Whenever the cluster protocol is disabled, a member switch forgets the learned cluster license as
well as peer information needed to compute license totals.
• If the switch start-up configuration is removed, a member switch forgets the learned cluster license
as well as peer information needed to compute license totals.
• If adding a new switch (with zero or non-zero installed license) to a group with at least one license
contributing switch down, the new group member will receive a different cluster license value.
For example, for a cluster of three switches (S1 = 6, S2 = 6 and S3 = 6 licenses), the group license
count is 18. If S1 goes down, the license count is still 18, since the license calculation is not initiated
if a member switch goes down. If S4 (with zero licenses) is introduced, S4 becomes part of the group
(can exchange updates and other packets), but has license count of 12 (NOT 18), even though S2 and
S3 still show a license count of 18. This should be an indicator a new member has been introduced
during a period when the redundancy group is not operating with all its license contributing members.
5.5 Layer 3 Mobility
Refer to the following sections to configure Layer 3 Mobility:
• Configuring Layer 3 Mobility
• Defining the Layer 3 Peer List
• Reviewing Layer 3 Peer List Statistics
• Reviewing Layer 3 MU Status
5.5.1 Configuring Layer 3 Mobility
Layer 3 mobility is a mechanism enabling a MU to maintain the same Layer 3 address while roaming
throughout a multi-VLAN network. This enables transparent routing of IP datagrams to MUs during their
movement, so data sessions can be maintained while they roam (in for voice applications in particular). Layer
3 mobility maintains TCP/UDP sessions in spite of roaming among different IP subnets.
A mobility domain comprises of a network of switches among which an MU can roam seamlessly without
changing its IP address. Each switch in the mobility domain needs a mobility domain string identifier so MUs
roaming between switches can retain their Layer 3 address and maintain application-layer connectivity.
When a MU enters a mobility domain (by associating with a switch), it is first assigned a home switch. The
home switch is responsible for assigning a VLAN for the MU and communicating the MU's mobility-related
parameters to the other switches in the mobility domain. The home switch does not change for the remainder
of the MU's presence in the mobility domain. All data packets transmitted/received by the MU including DHCP