Configuring Vlags - Lenovo CN4093 Application Manual

Configuring VLAGs

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CN4093 Application Guide for N/OS 8.3
When configuring VLAG or making changes to your VLAG configuration,
consider the following VLAG behavior:
 When adding a static Mrouter on VLAG links, ensure that you also add it on the
ISL link to avoid VLAG link failure. If the VLAG link fails, traffic cannot be
recovered through the ISL. Also, make sure you add the same static entry on the
peer VLAG switch for VLAG ports.
When you enable VLAG on the switch, if a MSTP region mismatch is detected
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with the VLAG peer, the ISL will shut down. In such a scenario, correct the
region on the VLAG peer and manually enable the ISL.
 If you have enabled VLAG on the switch, and you need to change the STP mode,
ensure that you first disable VLAG and then change the STP mode.
When VLAG is enabled, you may see two root ports on the secondary VLAG
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switch. One of these will be the actual root port for the secondary VLAG switch
and the other will be a root port synced with the primary VLAG switch.
 The LACP key used must be unique for each VLAG in the entire topology.
 The STG to VLAN mapping on both VLAG peers must be identical.
The following parameters must be identically configured on the VLAG ports of
both the VLAG peers:
 VLANs
Native VLAN tagging
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 Native VLAN/PVID
STP mode
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 BPDU Guard setting
STP port setting
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 MAC aging timers
Static MAC entries
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 ACL configuration parameters
QoS configuration parameters
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