mimmus,

Please reference the attached document "Configuring and Manageing Celerra Network High Availability.pdf"

I believe you will find what you need.

OK, I forgot to say that I configured FSN on the Celerra side

But I'm still not completely satisfied: if NIC/link fails, I have not a path to the active datamover.

For link/port redundancy on the data mover side configure LACP "trunks" (Celerra term) as the underlying FSN devices utilizing internal LACP link redundancy on the active FSN member.

it does not matter what you configure on Celerra, unless Celerra detects link state change it does not do anything with failover.  I had a situation where Celerra was connected to uplink switch that lost its backend connectivity to core switch, the link never went down but Celerra was hosed. Unless you get one of the new switches that allows LACP trunking between two physical switches you are at the mercy of link state.

Understood. The proposed LACP configuration on the data mover side was for data mover link redundancy on the active FSN device, nothing more.