D-Link DSN-6120 User Manual page 116

3. If iSCSI ports are assigned with VLAN ID before creating aggregation takes place,
aggregation will remove VLAN ID. You need to repeat step 1 and step 2 to set VLAN ID
for the aggregation group.
Assign VLAN ID to replication port

Please consult figure 5.11.3 of 5.11 Replication section for details.
Always make sure correct VLAN IDs are assigned to the correct network

ports (iSCSI, switch, and host NIC) to ensure valid connections.
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