Hi. We recently configured LACP with 4 interfaces in our dual controller FAS2240-4. We are running ONTAP 8.1.1. Recently we have started facing an issue where the vif interface is losing network connectivity but gets restored after a few minutes. We use PRTG to monitor our networks and it shows the vif interface as down during this period. The FAS is connected to Avaya ERS 5500 switches and are configured with LACP. Is there a configuration issue?
I am not deep in knowledge on the storage side but I did see your question also had an Avaya tag. I have ran into several issues from the networking side that have driven me away from good products with terrible vendor support.
If you are using ERS5xxx series the Jumbo frames are enabled by default and especially for SAN between servers and netapp limiting mtu can slow you down. At the very least verify that you match with network side. I also can't tell by your code if this is static or dynamic. Original 802.3ad is the first standard and is static, if using Nortel/Avaya this would be an MLT (Multi-Link-Trunk) or on a Catalyst it would be an Etherchannel. 802.1ax is dynamic and came out in 2008. It is a standard and vendors will usually point you to it. That said, if you are already using Auto-Negotiate for NICs (giving you Remote Fault Indication) and you are not planning on having over 8 connections in any single LACP group, static should work fine.
Back to Nortel/Avaya, the ERS code offers a global setting for LACP with the choice being "default" or "advanced". Be sure to choose default as advanced appears to only be of use between Avaya switches which as a global setting defeats the standard use to Storage in a Data Center. Spanning Tree can still create as many problems as it solves which is another reason I like the Static configuration, over a dynamic configuration.