SMB Multichannel vs Link Aggregation - what should you use?

In this video, I will be covering the differences between SMB Multichannel and link aggregation, what they both are, and when you should use one over the other. I have gotten a ton of comments on this topic, so hopefully it clears up some confusion! This video covers all types of link bonding, including LAGG, LACP, Bonding, Link Aggregation and Fail Over.
Hire Me! www.spacerex.co/hire-me/?utm_...
Join the forums: forums.spacerex.co/
Forum post mentioned: forums.spacerex.co/t/smbv3-mu...
Other videos mentioned:
SMB Multichannel Overview and Testing: • DOUBLE YOUR Performanc...
Products mentioned:
2.5 GbE adapter used for laptop*: amzn.to/3rI0lOv
#nas #smbmultichannel #lacp
TOC
00:00 Introduction
01:39 Redundancy
03:36 Throughput
06:34 Load Balancing
08:21 How to enable SMB Multichannel
10:06 Drawbacks of SMB Multichannel
11:43 How to enable Link Aggregation
12:23 Dynamic Link Aggregation (LACP)
13:40 Summary of when to use which solution
14:31 A quick clarification and test
17:06 Conclusion
*These are affiliate links, which means that if you purchase a product through one of them, I will receive a small commission (at no additional cost to you). Thank you for supporting my channel!

[@dukdukgoos]

My setup: Synology DS918+ with two 1Gbps connections to router, Windows 10 laptop with one 2.5Gbps connection to router, SMB multichannel enabled. I get more than 1Gbps throughput between NAS and laptop, but not the full 2Gbps... more like 1.75-1.8. Definitely Windows is using more than one of the connections to the NAS though. When looking at the Resource Monitor in DSM I can see both connections being used.

[@TazzSmk]

check cpu usage in Windows, and also if your network interface in Windows has RSS (receive side scaling) enabled (which basically does multi-core cpu load-balancing of network I/O), that said, around 1.8Gbit is about correct of what you can realistically get from dual 1Gbe connection

[@monsterous289]

Even with a 1Gbps connection, TCP/IP and UDP frame headers will take up anywhere from 5-10% of the data connection, giving a max useful data throughput of around 910Mbps. 1.7-1.8Gbps is absolutely expected.

[@christians6843]

Thanks for pointing out one cannot use both at the same time. I just read through some qnap manuals and there was no hint about it.

[@thomascanty4649]

Always helpful, thanks SpaceRex!!

[@CapsLock33]

thanks always for the tips and trick. You are the MAN SPACEREX!!

[@SpaceRexWill]

Happy to help!

[@ktoscos1404]

Hi spacerex, Lacp uses hash from l2 l3 or l3+l4 headers to chose link for specific connection. Lacp does not use any form of balacing "by" throughput. By the way I really like your videos !

[@ryguyver]

Fantastic, thank you so much for clarifying all this info! :)

[@JoeZelMusic]

Change MTU size on all adapters (Synology and Windows) to 4088. Seems to make a huge difference with initial access time. Worth trying for that intermittent video scrubbing issue mentioned in the video. The slowness of opening shared folders from the parent UNC path seems to respond much quicker. That's where I noticed the slowness quirk. Thanks for the video and covering all the basics!

[@brmakers]

Greetings from Brazil. I just bought a 1522+ and I'm watching all of your videos. I'll use the NAS to backup all my KZbin channel videos that are also on my PC. Also use as a home server for the family. I know one nas is not a backup but I have 2 14tb drives on my PC in raid0. The question is... My PC is connected to my router (Asus AX11000) via the 2.5gb connection both ports 2.5gb. the idea is to plug the 1522+ on two 1gb connections on the router... Will it work? Thanks for the awesome content. Best regards, Marcello.

[@JavisoGaming]

Great video and info! Thank you!!, 😊

[@sacundim]

I've never been able to reliably get SMB Multichannel from a Mac with a 2.5Gbps adapter to a Synology with two 1Gbps connections. I know it can actually double throughput because I somehow once managed to get it to work: the Mac's `smbutil multichannel -a` showed two connections between the single 2.5Gbps interface and the two 1.0Gbps interfaces, and big file transfers were hitting the 200 MB/sec rates. But (a) I don't know exactly which of the steps that I did when trashing around (plugging and unplugging stuff) caused it to work, and (b) I can no longer reproduce it.

[@life-longpatriot8258]

What about a client with a motherboard that has 1Gbit, 5Gbit and 10Gbit NICs connected to a 10Gbit switch and talking to a DS1815 with 4 ports? Assuming that with only three NICs, the client would only be able to attain a max throughput of 3Gbit, my question is will the different speed nics in the client's PC cause an issue, or is it transparent to the NAS since it is handled by the 10Gbit unmanaged switch?

[@davidgarbutt1003]

I have DS1520+ with 4 1gb connections going into a (NETGEAR 10-Port Gigabit/10G Ethernet Unmanaged Switch (GS110MX) - with 8 x 1G, 2 x 10G/Multi-gig) this is then linked through the 10gb connection to another of the same switches. On the second switch i have connected it to my pc with a Sabrent 10gb thunderbolt 3 and when transferring files the max speed is about 350MB's per second (Windows 11)

[@dbaranovskiy]

Great explanation, thank you! Do you know how this would work if the client and the NAS are connected to two different switches? Would I need multiple connections between the switches too or is one fast connection enough?

[@TazzSmk]

I don't think you can connect two "dumb" switches with multiple cables, it would cause packet storm, or whatever it's called, my setup with multiple switches for well performing SMB Multichannel is like this: router - switch (1Gbit) switch - switch (1Gbit) each NAS and computer (PC, Mac...) has one 1Gbe connected to first switch and second 1Gbe connected to second switch

[@dbaranovskiy]

@@TazzSmk Thank you!

[@user-mm6vv3fs8x]

What if you have a DS1522+ which has 4 ports, could you set the first two ports to link aggregation and the last port as SMB multichannel?

[@trevoradams3378]

What about 2 x NAS (synology) , each with 2 connections with lacp, would backup between the 2 be at faster rate, I assume backup would not use SMB

[@realkunalkapoor]

I have the same problem with MacOS. I have a 2.5GB NIC connected to my Mac and my Synology has multichannel enabled with 2 x 1GB connections. However for some reason the Mac only negotiates 1 stream. 'smbutil -a' indicates that multichannel is enabled but one server NIC remains idle exactly like it is mentioned in the video. Does anyone have a fix for this?

[@urtesttube]

Macs cannot establish multichannel unless there are multiple NICs

[@life-longpatriot8258]

In windows 10/11, Will I see a theoretical 4 Gbit throughput on a client with a single 10Gbit NIC that is accessing a Synology DS1815 with 4, 1Gbit NICs through a 10Gbit switch? (You mentioned that you didn't think so and your testing was only with MAC OS) Also, will Synology Drive Sharesync between two Synology NASs also utilize SMB multichannel during a sync operation? That would really speed up syncing my older DS1815s with my RS3618. With my SA3400, RS3618, DS2419 and FS1018, I installed a 10Gbit NIC where needed and left the 1GBit ports unconnected, but now it sounds like in order to maximize SMB multichannel, I'd have to connect all of the unused ports, which would mean getting a bigger switch. Would SMB multichannel be able to combine different speed NICs in a single NAS? If I understood your description correctly, in order for me to maximize the 4 ports on each DS1815 with SMB multichannel in a Synology Drive Sharesync operation, I'd have to have 4 1Gbit NICS connected in the server (in this case, the RS3618), not just a single 10Gbit NIC. Since the RS3818 also has 4 1Gbit NICs, I could connect those, but I worry that the 10Gbit NIC would then be underutilized on the LAN (i.e. load balancing).

[@SpaceRexWill]

Awesome! Thanks for the info on windows! As for SMB Multichannel: 1) this only works with SMB, will not speed up Synology Drive share sync (neither would LACP if you just have one client and one server) 2) SMB multichannel only takes the fastest connection

[@life-longpatriot8258]

@@SpaceRexWill Wow, if SMB multi ONLY uses the fastest connection, then it's really useless enabled on a NAS that has 4 1Gbit NICS and one 10Gbit NIC. That's a very useful piece of information to know. Thanks! Saved me a lot of useless wiring and a new, bigger 1Gbit switch.

[@gund89123]

I have DS918+, compared file loading times for large no of pictures using SMB Multichannel & NFS on my MBP. It took 20 mins to show files (30K) using SMB. < 2 mins using NFS. I verified that I was using both network cables in Synology task manager. If you have large no of small files then nothing can beat NFS in performance.

[@SpaceRexWill]

SMB gets incredibly slow listing files in a single folder. its just not built for that at all

[@Cabinlab]

Other vendors (Microsoft, QNAP, etc.) explicitly recommended SMB multichannel for large media files, including 8k+ video. In your previous video on SMB multichannel, you mentioned the issue related to scrubbing NLE timelines over multiple 10Gbe channels. In that scenario, you may be running into a CPU/core bottleneck, as each 10Gb channel requests a seperate core. NLE timeline performance isnt necessarily about big files, but it's hard to say what you experienced without more information. I wonder if there's something in your config or Synology's implementation that's reducing performance in video editing.

[@bubblekill2311]

Hello, I have trouble with cloud sync it stop running from time to time, soo annoying :s Any idea to fix ?

[@ToTheWind]

I have a Mac Mini. It only has one ethernet port on the back. I assume that SMB would not work with this limitation?

[@SpaceRexWill]

on my MacOS system it would appear not to work with 1x 10gbe to 2x 1GbE

[@brianhansen6906]

Can I do smb multichannel with 2 wireless cards instead of wired connection? I’m currently in a situation where I can’t run Ethernet cables to my home office, but I have an extra wifi AX card laying around I can put in my desktop

[@brianhansen6906]

I guess we’re about to find out. Just hooked up my second network cable to the nas from the router and am about to install the extra wireless network card and test it.

[@brianhansen6906]

well, the wireless card appears faulty and my computer wouldn't recognize it. Oh well I didn't have high hopes of it working since normally with WiFi I think all clients share the data, although with WiFi 6 it sounds like maybe they're able to do multiple channels at the same time that would then allow higher bandwidth and for this to possibly work, but probably unlikely. Someday I'll look forward to when I can route network cables and I'll just do it that way.

[@SirDadbod]

So if i have a home main pc (2.5gb card)...with typical modem and gaming router (nighthawk x10)1gb card connected to a ds418 (older model with 1x usb 3.0 in back and 2 ethernet 1gb ports) with 2 family members on wifi pcs (1gb card each) using mapped drive to shared folder on nas,, If i want to take advantage of those ethernet cards (on ds418 and main pc) for uploading large files and folder to the nas,, can i benefit from smb multichannel or link aggregation so i can speed up my uploads and backups to drive, to usbshare1 folder uploads? With a usb dock 3.0 and full internal 7200 rom drive i get 50 to 80 mb data transfer... Im still learning so im wondering...do i hook up a second cat cable from main pc to ds418 and set up smb or link aggregation...? I dont edit files i just upload and backup tons of pictures videos and documents and organize mostly..?? thanks

[@gustersongusterson4120]

Is it worth it to use SMB multichannel with a wifi connection and a wired ethernet connection? For example a 1gb wired connection and a nearly 1gb AC wifi connection? I imagine latency would be even worse but this would just be for file transfers, backups and some audio production work which is generally pretty tolerant of disk latency.

[@SpaceRexWill]

They have to be the same speed to be used for multichannel, so wifi would not help

[@TazzSmk]

no, mixing wireless and wired connection is NOT recommended for SMB Multichannel

[@darkphotographer]

you came abaut 10 years late , was cool when you had only 1gb nic , link agragation work well when you have muliple clent hiting the same server but you need smart switch , , but smb multi work well pear to pear ,

[@timetravellingtoad]

Even better when you connect apples to oranges.

[@brianakers2719]

How would SMB work if you need to made another hop? Say you have 2x - gigabit switches in-between, I'm assuming one would need the same amount of connections going between the 2 switches?

[@life-longpatriot8258]

I'd been waiting for Synology to incorporate this in their OS for a long time to breathe new life into a couple of my older NASs, but I didn't realize that a client with a single 10Gbit NIC wouldn't see any benefit. That is a real limitation to its usefulness. I hesitate to remove the LACP bonds I currently have set up with those two DS1815s, because adding all of the additional cabling and bigger switch just to make it work seems like a tough sell.

[@pr0jectSkyneT]

Can you do link aggregation if your server has a 1Gbps and a 2.5Gbps port for a total of 3.5Gps?

[@Cerim112]

I am a bit confused isn’t this the same as bonding the two ethernet ports, and making them one?

[@SpaceRexWill]

LACP is, SMB Multichannel is not

[@ellenorbjornsdottir1166]

Before I watch: I think they are both tools in the toolbox. There's not an either/or - you can aggregate, and use multichannel SMB - right?

[@ellenorbjornsdottir1166]

hm. I suppose lagg doesn't cleanly sum up the bandwidths of the two links, hey? making the use of multichannel over multiple laggs less useful

[@dtownssqwe]

Is SMB Multichannel for PC to NAS only or NAS to NAS as well?

[@SpaceRexWill]

Pc to NAS only

[@dtownssqwe]

@@SpaceRexWill if you have two DS220+ what is the fastest way to transfer data between them? Is Link Aggr an option here?

[@life-longpatriot8258]

@@SpaceRexWill Wow, I didn't realize that! Makes it even less useful for me. I only really needed it for syncing my much older, slower NASs to the main server. I make Macrium images of my PCS' "C" drive every few months, and the .ISO images take forever to sync to the older NASs at 1Gbit since they are often over 100GB in size. I only power up the older NASs every month or so to sync to the main servers, and the idea that I could sync them at close to 400MB/sec instead of the usual 110MB/sec was very appealing,. That's what I thought SMB multi-channel was going to allow. Another dream crushed!

[@TedTremendous]

There is a pretty serious caption malfunction you will want to correct at 3:53 😂🤣😅

[@nicholasnormanholland5338]

Thank you very much for all these good contributions. Can I ask a question about your experience mentioned at 15:00? I've already googled a lot about it and can't find a clear answer. Some approve of it and others don't. Synology recently posted this article kzbin.info/www/bejne/Z6TUla2YrL6eoJo online. There from 1:04 it is clearly stated that SMB Multichannel with NAS 2x 1GB on a 10GB switch, the client with 1x10GB on switch, would work. I don't know who to ask and I'm very irritated. What do you think?