I see the gulde "Ethernet Storage Design Considerations and Best Practices for Clustered Data ONTAP Configurations",
It say ": If you use iSCSI (RFC 3720) in clustered Data ONTAP, there are two methods to achieve path redundancy. One method is to use IFGRPs to aggregate more than one physical port in partnership with a Link Aggregation Control Protocol (LACP)–enabled switch. Another method is to configure hosts to use Microsoft Multipath I/O (MPIO) over multiple distinct physical links. Both of these methods allow a storage controller and a host to use aggregated bandwidth, and both can survive the failure of one of the paths from host to storage controller. However, MPIO is already a requirement for using block storage with clustered Data ONTAP, and the use of MPIO has the further advantage of no additional required switch configuration or port trunking configuration. Also, the use of an IFGRP for path management when you use iSCSI is not supported; again, you should use MPIO with iSCSI. However, the use of an IFGRP as a port for an iSCSI LIF is supported."
What mean is :the use of an IFGRP for path management when you use iSCSI is not supported."
Sorry it has taken a while to get back to you - my understanding is that this means is that LACP should not be used for client connectivity for links running iSCSI sessions to targets, but it is acceptable to use LACP for the connection from the controller (target) to the switching infrastructure that clients connect to.