Field Notice-2023-482 - VOSS/Fabric Engine releases prior to 8.7.0.0 and 8.5.2 lose SMLT configuration on reboot if DHCP Snooping and ip dhcp-snooping trusted are configured on 2 or more VLANs on a MLT
Summary
VOSS Fabric Engine platforms lose SMLT configuration on reboot if DHCP Snooping is enabled on 2 or more VLANs on the MLT and “ip dhcp-snooping trusted” is also configured.
This issue impacts VOSS/Fabric Engine versions prior to 8.7.0.0 and 8.5.2.
Impact
The configuration file will not reflect SMLT configuration on the affected MLTs when users encounter this condition.
This will result in link aggregation across chassis not being present if the switch is restarted and the configuration reloaded, leading to elevated CPU utilization and will cause potential traffic impact.
Products Affected
All VOSS/Fabric Engine platforms
Software Affected
VOSS/Fabric Engine releases prior to 8.7.0.0 and 8.5.2
VOSS/Fabric Engine 8.6.x releases are affected.
Symptoms
This problem results in a latent error in the configuration file which will result in SMLT configuration not being present after reboot or upgrade.
Workaround
If the SMLT configuration is impacted then it should be added again after the user reboots or upgrades.
The “ip dhcp-snooping trusted” command can be removed from the MLT configuration, and the configuration should be saved prior to restarting or upgrading the switch to avoid this issue.
Solution
This issue is fixed in release 8.5.2, 8.7.0.0 and later code.
Configuration should be saved and validated following upgrade to 8.5.2, 8.7.0.0 or later code.
Please see the full Field Notice article here for more details.
