Alternative to SMLT

[NickH]

We want to form an MLAG over a pair of VSPs but to implement SMLT you need to disable IS-IS to configure the smlt peer and vIST. This would mean downtime whilst configuration is completed. Is anyone aware of an alternative MLAG solution on the VSPs that doesn't require IS-IS to be disabled?

[WillyHe]

Hello Nick,
There is no alternative way to make an MLAG connection to ISIS enabled switches, you must create the vIST link so the VSP switches can form an SMLT cluster.
When in "SPBM/SMLT" cluster configuration they start exchanging link state information for the SMLT enabled ports, like MLAG enabled switches do.

When actually the connections to both VSP switches are redundant then it is no problem to apply one by one the SMLT configuration to them without interrupt traffic, the "other" switch take over traffic forwarding during switch reconfiguration.
In case of single connected devices then you have to consider how critical these connection are.

Hope it helps
regards
WillyHe