Dell S4048-ON, Configuration Manual

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Description Behavior at Peer Up Behavior During Run Time Action to Take
information, refer to the
Release Notes for this release.
VLT LAG ID is not configured
on one VLT peer
A syslog error message is
generated. The peer with the
VLT configured remains active. A syslog error message is
generated. The peer with the
VLT configured remains active. Verify the VLT LAG ID is
configured correctly on both
VLT peers.
VLT LAG ID mismatch
The VLT port channel is
brought down.
A syslog error message is
generated.
The VLT port channel is
brought down.
A syslog error message is
generated.
Perform a mismatch check
after the VLT peer is
established.
Reconfiguring Stacked Switches as VLT
To convert switches that have been stacked to VLT peers, use the following procedure.
1. Remove the current configuration from the switches. You will need to split the configuration up for each switch.
2. Copy the files to the flash memory of the appropriate switch.
3. Copy the files on the flash drive to the startup-config.
4. Reset the stacking ports to user ports for both switches.
5. Reload the stack and confirm the new configurations have been applied.
6. On the Secondary switch (stack-unit 2), enter the command
stack-unit 2 renumber 1
.
7. Confirm the reload query.
8. After reloading, confirm that VLT is enabled.
9. Confirm that the management ports are interconnected or connected to a switch that can transfer Heartbeat information.
Specifying VLT Nodes in a PVLAN
You can configure VLT peer nodes in a private VLAN (PVLAN). VLT enables redundancy without the implementation of Spanning
Tree Protocol (STP), and provides a loop-free network with optimal bandwidth utilization.
Because the VLT LAG interfaces are terminated on two different nodes, PVLAN configuration of VLT VLANs and VLT LAGs are
symmetrical and identical on both the VLT peers. PVLANs provide Layer 2 isolation between ports within the same VLAN. A PVLAN
partitions a traditional VLAN into sub-domains identified by a primary and secondary VLAN pair. With VLT being a Layer 2
redundancy mechanism, support for configuration of VLT nodes in a PVLAN enables Layer 2 security functionalities. To achieve
maximum VLT resiliency, you should configure the PVLAN IDs and mappings to be identical on both the VLT peer nodes.
The association of PVLAN with the VLT LAG must also be identical. After the VLT LAG is configured to be a member of either the
primary or secondary PVLAN (which is associated with the primary), ICL becomes an automatic member of that PVLAN on both
switches. This association helps the PVLAN data flow received on one VLT peer for a VLT LAG to be transmitted on that VLT LAG
from the peer.
You can associate either a VLT VLAN or a VLT LAG to a PVLAN. First configure the VLT interconnect (VLTi) or a VLT LAG by using
the
peer-link port-channel id-number
command or the VLT VLAN by using the
peer-link port-channel id-
number peer-down-vlan vlan interface number
command and the
switchport
command. After you specify the
VLTi link and VLT LAGs, you can associate the same port channel or LAG bundle that is a part of a VLT to a PVLAN by using the
interface interface
and
switchport mode private-vlan
commands.
When a VLTi port in trunk mode is a member of symmetric VLT PVLANs, the PVLAN packets are forwarded only if the PVLAN
settings of both the VLT nodes are identical. You can configure the VLTi in trunk mode to be a member of non-VLT PVLANs if the
VLTi is configured on both the peers. MAC address synchronization is performed for VLT PVLANs across peers in a VLT domain.
Virtual Link Trunking (VLT)
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