Lenovo ThinkSystem NE2552E, Application Manual

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NE2552E Application Guide for ENOS 8.4
Static LAGs
When you create and enable a static LAG, the LAG members (switch ports) take on
certain settings necessary for correct operation of the aggregation feature.
Before Configuring Static LAGs
Before you configure your LAG, you must consider these settings, along with
specific configuration rules, as follows:
 Read the configuration rules provided in the section, “Static LAG Configuration
Rules” on page 164 .”
 Determine which switch ports are to become LAG members (the specific ports
making up the LAG).
 Ensure that the chosen switch ports are set to
enabled
.
 Ensure all member ports in a LAG have the same VLAN configuration.
 Consider how the existing Spanning Tree will react to the new LAG
configuration. See “Spanning Tree Protocols” on page 173 for configuration
guidelines.
 Consider how existing VLANs will be affected by the addition of a LAG.
Static LAG Configuration Rules
The aggregation feature operates according to specific configuration rules. When
creating LAGs, consider the following rules that determine how a LAG reacts in
any network topology:
 All LAGs must originate from one network entity (a single device or multiple
devices acting in a stack) and lead to one destination entity. For example, you
cannot combine links from two different servers into one LAG.
 Any physical switch port can belong to only one LAG.
 Depending on port availability, the switch supports up to 32 ports in each LAG.
 Internal ports (INT x ) and external ports (EXT x ) cannot become members of the
same LAG.
 Aggregation from third ‐ party devices must comply with Cisco
®
EtherChannel
®
technology.
 All LAG member ports must be assigned to the same VLAN configuration
before the LAG can be enabled.
 If you change the VLAN settings of any LAG member, you cannot apply the
change until you change the VLAN settings of all LAG members.
 When an active port is configured in a LAG, the port becomes a LAG member
when you enable the LAG. The Spanning Tree parameters for the port then
change to reflect the new LAG settings.
 All LAG members must be in the same Spanning Tree Group (STG) and can
belong to only one Spanning Tree Group (STG). However if all ports are tagged ,
then all LAG ports can belong to multiple STGs.