The mgwd user space process is responsible for managing the cluster configuration and providing the management interface for ONTAP. If this process crashes, it may generate a core dump file in the /mroot/etc/mgwd/core directory of the node. To access this directory, you need to log in to the systemshell, which is a Linux shell that runs on the node. The systemshell can be accessed by logging in to the nodeshell using the node console and then running the systemshell command. The nodeshell is a custom shell that provides access to ONTAP commands and utilities. The service processor and the clustershell are not relevant for collecting core dumps from the mgwd process. Reference = ONTAP 9 Cluster Administration, page 29-30; ONTAP 9 Troubleshooting Guide, page 23-24.

IQN stands for iSCSI Qualified Name, which is a unique identifier for an iSCSI initiator or target1.
ONTAP uses IQN to authenticate and authorize iSCSI sessions2.
If two hosts have the same IQN, they will cause a conflict and ONTAP will reject the new session request from the second host3.
This will result in the host losing the connection to the iSCSI target and then reporting that the session was reestablished, as shown in the exhibit.
To avoid this problem, each host should have a unique IQN. Reference:
iSCSI Qualified Name (IQN) - NetApp
iSCSI authentication and authorization - NetApp
Troubleshooting iSCSI issues - NetApp
[Configuring iSCSI initiators - NetApp]