Thanks to certain beginner-friendly distros, Network-Attached Storage systems are easier to set up than ever, and you can get a budget-friendly backup server without shelling out wads of cash on the hardware. However, the complexity of these storage servers goes up a notch once you step into the nitty-gritty of NAS services. And I don’t mean virtualization or snapshots either – there’s a ton of cool services that can elevate your NAS experience, provided you’re willing to put in some extra effort to configure them.

SMB multichannel is one such feature that’s not only locked behind a barrage of menus, but also needs some convoluted pre-requisites. But if you’re good with home networks and have a semi-decent storage server with spare network interfaces, it’s a service worth checking out.

What’s SMB multichannel, anyway?

A way to boost your transfer speeds

Let’s say you’ve got a couple of spare Ethernet ports on your NAS and at least two such connections on your PC. Well, SMB multichannel lets you combine all the ports between a client PC and a NAS server in a single SMB connection. While fault tolerance is an obvious advantage of such a setup, the biggest draw of SMB multichannel is that you can bolster the file transfer speeds between the server and a (single) client. As such, it’s pretty effective when your workloads involve heavy SMB transfers where you can put multiple 1G or 2.5G Ethernet ports to good use.

And no, it’s not link aggregation

Before I read all the documentation on SMB multichannel, I figured it was similar to link aggregation. Technically, link aggregation and SMB multichannel can improve your NAS’ fault tolerance by leveraging a couple of network interfaces, but they serve entirely different purposes.

Link aggregation involves combining the network ports on your NAS into a single logical link, and provides increased throughput to all the clients (emphasis on all) in your home network. So, rather than increasing the transfer speeds of your NAS by turning 2x 1G ports into 2G connections, it boosts the amount of bandwidth that can flow into the storage server, making it better when you’ve got multiple devices attempting to read/write data to it.

Meanwhile, SMB multichannel is ideal for setups where you need high-speed file transfers between a single client-server pair. Not to mention, you’ll need more than one network interface on both the NAS server and your PC (or whatever device you’re using as the client).

Both services are also mutually exclusive for your home network, and you’ll have to disable link aggregation before configuring SMB multichannel. Then there’s the other, more complicated pre-requisite…

You’ll need two subnets, though

VLANs are your best friends

TrueNAS requires you to configure at least two different subnets for SMB multichannel, and although you can use a couple of workarounds, using the same subnet can land you with some performance issues. Essentially, your setup will require distinct subnets, with each one featuring a pair of client and NAS network interfaces. Take my setup, for instance:

Subnet 1 has 192.168.0.1 as the gateway, with 192.168.0.71 being the IPv4 address of the NIC on my PC and 192.168.0.97 belonging to one of the two network interfaces on my TrueNAS workstation. Likewise, the other subnet has 192.168.8.82 as the NAS IPv4 address and 192.168.8.198 as the NIC on my PC, with 192.168.8.1 being the gateway.

Unfortunately, setting up the subnets can be a bit of a challenge if you’re not accustomed to tinkering with home networks. I used my Zyxel managed switch to create separate VLANs for each pair of PC-NAS network interfaces. Afterward, I headed to the VLAN section within my OPNsense router and created two VLANs featuring its LAN port as the Parent interface and the same VLAN tags as the VIDs on my Zyxel switch. After enabling each interface, I set a Static IP for them and configured DHCP to assign the IPv4 addresses to my NAS and PC interfaces.

Setting up SMB multichannel

It’s a piece of cake in TrueNAS

Once I’d gone through the process of setting up different VLANs, the rest of the procedure was relatively simple. I clicked on the menu button inside the Windows (SMB) Shares section on the TrueNAS web UI and chose Configure Service. Tapping the Advanced option inside the SMB settings columns revealed Multichannel, which I promptly enabled before restarting the SMB server.

With SMB multichannel configured on TrueNAS, I signed in to the network share on my PC and opened the Windows terminal. I quickly ran Get-SmbServerConfiguration | Select EnableMultichannel and Get-SmbClientConfiguration | Select EnableMultichannel to enable the facility on my PC before executing Get‑SmbMultichannelConnection to confirm whether it's working.

Take your NAS game to the next level with some neat features

Besides SMB multichannel, there are a couple of cool options you can tinker with in a NAS. My favorite is RAM (and to a lesser extent, SSD) caching, which can grant a significant boost to HDD speeds. If you value backups as much as I do, TrueNAS and fellow compatriots of the NAS landscape include dedicated snapshot utilities to safeguard all the data stored on your storage server.