Link aggregation sounded quite helpful when I first heard of it. Take two network cables, plug them into your NAS, tie them together with some magical configuration, and voilà — you have double the transfer speeds. At least, that’s the impression I had until I tried it on my own.

The reality was close to those expectations, but it was surely much less dramatic. Link aggregation won’t turn a gigabit NAS into a two-gigabit rocket for a single client device. What it actually does is much smarter: it makes the connection better for everyone using the NAS simultaneously. And for a shared setup like mine, link aggregation turned out surprisingly useful.

What I expected vs. what I got

Clearing up the misconceptions

When I read the literature on link aggregation, I assumed that it would double the speed — literally — on single-device transfers, especially the larger ones. Copying a huge 50GB video file from my laptop to the NAS, I thought, would be done in half the time as before. But it couldn’t be further from the truth. My transfers were still capped at 1Gbps, because that’s the limit for each lane, even if the ‘highway’ now has two lanes.

But what really changed was not on my main laptop, but the other devices in my home. While I was transferring that video, another laptop of mine started to run its weekly backup schedule. Usually, it would choke the network and slow things down for everyone using the NAS, be it these two laptops or someone streaming a movie on Plex in the living room.

However, with link aggregation, the NAS handled things quite gracefully this time. Not only did the transfer happen at full speed, but the backup also completed on time. Neither of them was fighting for the bandwidth to get the task completed at the earliest, and failing.

Where it actually made a difference

The kind that often becomes apparent

As I previously said, the biggest win has been simultaneous use. Now that I am sharing my NAS with my entire family for backing up media and local media streaming, it needs link aggregation more than ever. And setting it up gave me instant results.

For starters, backup tasks don’t bottleneck the network anymore. They don’t step on each other’s toes — I can run multiple devices and media backups at once without the speeds taking a nosedive.

Even streaming media on Jellyfin and Plex has improved quite a bit. Earlier, when someone would fire up Plex to watch the latest episode of Game of Thrones in 4K during working hours, the NAS would come to a halt, but not anymore. No one has complained about random stutters mid-stream anymore.

Things certainly don’t feel like ‘twice as fast’ as I had imagined earlier, but transfers fly — especially when a lot of them happen at the same time. And that’s what a meaningful quality-of-life upgrade is.

Bonus perks I didn’t think about

Oh, the extras!

Sure, link aggregation adds another lane to ease the traffic on your congested highway, but that extra lane also helps in another nice way. The second LAN connection offers incredible redundancy to your system. On the off chance that one of the cables or ports dies, the NAS doesn’t suddenly go dark. The other connection will take over, so your work isn’t affected, even on a busy Tuesday morning.

In a way, it also helps me save cash in the short term and future-proof my NAS. Instead of having to upgrade my NAS to one that supports a faster LAN port or using expensive first-party accessories to upgrade the existing port, I can simply connect the second 1GbE LAN port to the network switch for an immediate better experience. And over time, as I add more devices to my home relying on the NAS or add more high-res content, the network won’t have to struggle to keep up; there would already be enough bandwidth to spare for a very long time.

Having said that, setting up link aggregation itself doesn’t come without catches. It’s certainly not a switch that you flip and get going. First of all, you need a hardware setup that supports LACP (the standard protocol) at every touchpoint, from the NAS to the router, and the network switch in between. Even your cabling has to be able to work with the setup. And above all, you need to have loads of patience to test out everything over and over until everything works just as expected.

It’s worth every penny

And the time spent

Cent percent! But not for the reasons I had imagined early on. Link aggregation didn’t make single-device and file transfers fast for me, and neither is it supposed to. What it has indeed helped with is the shared experience. Now everyone can use the NAS simultaneously without impacting each other’s experience, no matter what they’re doing. All the backups, streaming, and transfers can happen together without the NAS starting to breathe hard.

But if you don’t have such expansive needs and are a solo user of the NAS, you’d be better off without setting up and using link aggregation. It won’t bring any meaningful improvement to your NAS setup, and the effort to set it up will all go in vain. Remember: it doesn’t widen the existing network lane but adds another one for more cars (bits of data) to cross — there’s a difference.