White Papers

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0 programmable-mux programmable-mux
Dell#
The IOA is now ready for PMUX operations.
Configuring the Commands without a Separate User
Account
Starting with Dell Networking OS version 9.3(0.0), you can configure the PMUX mode CLI commands without having to
configure a new, separate user profile. The user profile you defined to access and log in to the switch is sufficient to configure
the PMUX mode commands.
The IOA PMUX Mode CLI Commands section lists the PMUX mode CLI commands that you can now configure without a
separate user account.
Virtual Link Trunking (VLT)
VLT allows physical links between two chassis to appear as a single virtual link to the network core. VLT eliminates the
requirement for Spanning Tree protocols by allowing link aggregation group (LAG) terminations on two separate distribution
or core switches, and by supporting a loop-free topology. VLT provides Layer 2 multipathing, creating redundancy through
increased bandwidth and enabling multiple parallel paths between nodes and load-balancing traffic where alternative paths exist.
NOTE:
When you launch the VLT link, the VLT peer-ship is not established if any of the following is TRUE:
● The VLT System-MAC configured on both the VLT peers do not match.
● The VLT Unit-Id configured on both the VLT peers are identical.
● The VLT System-MAC or Unit-Id is configured only on one of the VLT peers.
● The VLT domain ID is not the same on both peers.
If the VLT peer-ship is already established, changing the System-MAC or Unit-Id does not cause VLT peer-ship to go down.
Also, if the VLT peer-ship is already established and the VLT Unit-Id or System-MAC are configured on both peers, then
changing the CLI configurations on the VLT Unit-Id or System-MAC is rejected if any of the following become TRUE:
●
After making the CLI configuration change, the VLT Unit-Id becomes identical on both peers.
● After making the CLI configuration change, the VLT System-MAC do not match on both peers.
When the VLT peer-ship is already established, you can remove the VLT Unit-Id or System-MAC configuration from either
or both peers. However, removing configuration settings can cause the VLT ports to go down if you configure the Unit-Id or
System-MAC on only one of the VLT peers.
Overview
VLT allows physical links between two chassis to appear as a single virtual link to the network core or other switches such as
Edge, Access, or top-of-rack (ToR).
VLT reduces the role of spanning tree protocols (STPs) by allowing link aggregation group (LAG) terminations on two separate
distribution or core switches, and by supporting a loop-free topology. (To prevent the initial loop that may occur prior to VLT
being established, use a spanning tree protocol.
VLT provides Layer 2 multipathing, creating redundancy through increased bandwidth, enabling multiple parallel paths between
nodes and load-balancing traffic where alternative paths exist.
Virtual link trunking offers the following benefits:
● Allows a single device to use a LAG across two upstream devices.
● Eliminates STP-blocked ports.
● Provides a loop-free topology.
● Uses all available uplink bandwidth.
PMUX Mode of the IO Aggregator
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