Synology NAS supports multi-LAN, allowing you to combine those LAN interfaces using the Link Aggregation technology. Link Aggregation increases the bandwidth of your Synology NAS by aggregating multiple network interfaces and provides traffic failover to maintain network connection in case the connection is down. After your LAN interfaces are combined, you will see a new interface named Bond at Control Panel > Network > Network Interface, which could be configured as you would with other interfaces (such as LAN or PPPoE).

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