TS-653d and Port Trunking w/ Unifi SDM

Port Trunking and SMB Multichannel are designed for different purposes. While they can be enabled at the same time, they may not deliver the expected performance benefits. In some network environments, enabling both may even lead to unstable connections.

Port Trunking (e.g., 802.3ad/LACP) combines multiple physical network cables into a single logical link and presents only one IP address to the outside. However, SMB Multichannel relies on multiple distinct IP addresses to establish multiple channels. As a result, when Port Trunking is enabled, SMB only detects a single path and cannot initiate multiple TCP connections, thus losing the advantages of multichannel transmission.

We recommend choosing the appropriate method based on your actual usage scenario:

  • For environments with multiple users accessing the NAS simultaneously or businesses with a network switch setup, Port Trunking is recommended to improve overall performance and stability.
  • For individual users or small offices focused on improving file transfer speed between a single client and the NAS, SMB Multichannel is the better choice to shorten transfer time and fully utilize available bandwidth.

Hope this helps clarify the difference!