Register for the iXsystems Community to get an ad-free experience and exclusive discounts in our eBay Store.
Resource icon

LACP ... friend or foe?

Mirfster

Doesn't know what he's talking about
Joined
Oct 2, 2015
Messages
3,226
Thanks
591
#41
Slightly off-topic question : Would you recommend using LACP between two Netgear GS724T switches, or is it also worthless ?
My understanding is, if I aggregate 4 ports, switches will have 4 Gb/s connection between them.
Doesn't this model have dedicated SFP Uplink Ports?
 

Marcet

FreeNAS Experienced
Joined
May 31, 2013
Messages
193
Thanks
8
#42
Doesn't this model have dedicated SFP Uplink Ports?
Yes it does. But these ports are 1 Gb/s if I make no mistake.
They are dedicated to long distance.
 

Mirfster

Doesn't know what he's talking about
Joined
Oct 2, 2015
Messages
3,226
Thanks
591
#43

Marcet

FreeNAS Experienced
Joined
May 31, 2013
Messages
193
Thanks
8
#44

depasseg

FreeNAS Replicant
Joined
Sep 16, 2014
Messages
2,864
Thanks
487
#45
My understanding is, if I aggregate 4 ports, switches will have 4 Gb/s connection between them.
It will suffer the same constraint. Meaning it isn't a 4Gb/s pipe, it's still 4 x 1Gb/s pipes.
 

Marcet

FreeNAS Experienced
Joined
May 31, 2013
Messages
193
Thanks
8
#46
It will suffer the same constraint. Meaning it isn't a 4Gb/s pipe, it's still 4 x 1Gb/s pipes.
Ok, I understand. But in case of a switch, I believe the chance for it uses more than 1 Gb/s is more likely to happened. Am I right ?
 

depasseg

FreeNAS Replicant
Joined
Sep 16, 2014
Messages
2,864
Thanks
487
#47
Ok, I understand. But in case of a switch, I believe the chance for it uses more than 1 Gb/s is more likely to happened. Am I right ?
It depends on your environment. A single connection going through the 2 switches will be limited to 1Gb/s. If you have lots of machines on both switches then yes it will likely help.
 

Marcet

FreeNAS Experienced
Joined
May 31, 2013
Messages
193
Thanks
8
#48
It depends on your environment. A single connection going through the 2 switches will be limited to 1Gb/s. If you have lots of machines on both switches then yes it will likely help.
Thanks for this clarification.
 

PrincePaul

FreeNAS Experienced
Joined
Feb 26, 2012
Messages
225
Thanks
11
#49
So if I'm getting it right: LACP means an auto LAG Config, which dynamically/constantly changes or adapts if for example one connection fails by sending LACP packages.
A normal LAG is configured once by hand and always stays like that, so if we have the same case and one port goes down, then you manually have to fix that.

So LACP is just easier to use, but a hand configured LAG should get the same performance?

I'm asking because the TP-Link TL-SG1016DE supports LAG but no LACP, so if manually configured, then I still should be able to tie the 4 networkcards from a Supermicro A1SAi-2550F together and have full gigabit speed on 4 clients simultaneously, right?

Or should I get an LACP capable switch? Haven't bought anything yet.
802.3ad means LACP capable, right?
 

jgreco

Resident Grinch
Moderator
Joined
May 29, 2011
Messages
11,656
Thanks
2,946
#50
What any individual vendor means by link aggregation is basically that the marketing department takes what the engineering department tells them (which might be "static link aggregation"), then they see the word "aggregation", so then they trumpet that the product is capable of link aggregation, and someone else tacks on "LACP."

This is why I often cynically assume that especially low end products claiming LACP might not actually be LACP. But as previously noted, even LACP doesn't mean you'll

be able to tie the 4 networkcards from a Supermicro A1SAi-2550F together and have full gigabit speed on 4 clients simultaneously,
No version of LACP ever means that. It means that there is theoretically the potential for that to happen, if you're really lucky or if you're really OCD and arrange things just perfectly so that it happens in practice. On average, if you want four network cards in an LACP to serve clients and be maxxed out, you probably need more like a dozen active clients, and even then they won't be evenly served. You probably need dozens of active clients to get approximately "fair" service.
 

PrincePaul

FreeNAS Experienced
Joined
Feb 26, 2012
Messages
225
Thanks
11
#51
ok, thanks for your reply.

With static link aggregation there is the problem with packages send not in order, right?
Which LACP prevents - so I should be better off with a Switch which officially supports 802.3ad.
These Zyxel 1900 Series Switches for example looking quiet nice for the price.
 
Joined
Apr 4, 2017
Messages
13
Thanks
0
#52
Hello guys!

Great read about LACP.
I am finally thinking (not concluding) that LACP might be troubling my setup. Though, I have read through this thread and the forum and can't find anyone facing the same issue as me.
I am posting a link to my problem. Thanks if anybody can have a suggestion about it.

https://forums.freenas.org/index.php?threads/afp-binding-issue.53857/
 

cods69

FreeNAS Aware
Joined
Sep 11, 2016
Messages
50
Thanks
15
#53
I finally got LACP going on my c2750d4i using a RT-AC88U.
Turns out it's far easier and less messy to configure the Link Aggregation through the startup console option 1/2 in IPMI than via the GUI.
Even tweaking it via console menu after initially setting up in GUI (and losing connection) gave me much grief.
First shot setting it up via console worked perfectly and gave me less interrupted control over the config.

Impressed with some of the tests too, FWIW.
 
Last edited:
Joined
Oct 11, 2016
Messages
88
Thanks
4
#54
UPDATE: I'm one of these REAL special kind of people.
I told the Netgear the WRONG ports to LAGG. I have (1) out of the (2) correct..
Thanks for the sounding board!! LOL

So i'm finally messing around with LAGG on my old server with the latest stable Freenas installed (U4).
I have a Netgear GS108T switch that supports LACP.
I was able to set up my LAGG in FN and turn everything on in my Netgear to get LAGG running.
Now, i KNOW.. my crappy Freenas system is NOT to code, I don't use it other then to test things out so don't freak out on me!
upload_2017-10-5_23-4-31.png


I have looked everything over and played with setting but I keep getting this message.

So, I did "ifconfig" and found this..
upload_2017-10-5_22-53-22.png


I see that for whatever reason, only (1) of my ports are working. So I went and did more digging on my Netgear but couldn't find any more "things" to mess with.
I have the following info from my Netgear. You'll notice that it too only shows (1) port active. But if I change the LAG type to "Static" I loose connection to my Freenas but it shows activity on BOTH ports...
upload_2017-10-5_22-56-28.png

upload_2017-10-5_22-57-56.png

upload_2017-10-5_22-58-25.png

upload_2017-10-5_22-59-11.png


Only thing I can think of is do I need to type "up" in the options in the Freenas LAGG section?
upload_2017-10-5_23-1-38.png

upload_2017-10-5_23-2-9.png


Ok, sorry for all the pictures, I just want to make sure I gave any info that I have in front of me.

Thanks for all the help guys!
 

Attachments

Last edited:

RegularJoe

FreeNAS Experienced
Joined
Aug 19, 2013
Messages
184
Thanks
4
#55
LACP to get 4 1gig ports to deliver 4gb of iSCSI traffic to VMware storage for VMware guests is the only way to make this work. VMware has a feature in the enterprise license and the vSphere Distributed vSwitch. The load balance algo is : "Route based on physical NIC load" The speed is only 4gb when you use 4 VLAN's with 4 subnets on the FreeNAS side. You are talking about a lot of work, easier to just go get a 10gig nic from ebay and call it a day. LOL

Any other benefit you will get you need to have hundreds or thousands of end stations requesting data from your LACP interface to reap LACP benefits. LACP is fine for redundancy to your Ethernet infrastructure.
 

RegularJoe

FreeNAS Experienced
Joined
Aug 19, 2013
Messages
184
Thanks
4
#56
Cisco switches work, I have had too many issues with whitebox switches and generic ones. The best option is to just buy a Cisco switch from ebay. Whitebox fun starts when you try to do a SNMP walk and it locks up the control plane and ssh/telnet interface. Whitebox fun never ends.
 

RegularJoe

FreeNAS Experienced
Joined
Aug 19, 2013
Messages
184
Thanks
4
#57
for VMware and iSCSI when using FreeNAS as the SAN it does work because VMware will round robin the packets across all of the interfaces that it sees the LUN is bound to. This is one need at the SAN application layer.
 
Joined
Dec 16, 2012
Messages
49
Thanks
2
#58
Hi all,

Did anyone manage to connect LACP from FreeNAS to a Ubiquity EdgeSwitch portChannel ?
I was able to ping the FreeNAS and vice versa, but no DHCP allocation and even if I manually set the IP, the web interface was not accessible.
any clue?
 
Last edited by a moderator:

RegularJoe

FreeNAS Experienced
Joined
Aug 19, 2013
Messages
184
Thanks
4
#59
White-box fun! Do you have a Cisco switch you can test with ? Even at 10/100 if the Cisco works the white-box should as well. Is that switch a Broadcom, Brocade or VXWorks based switch?
 

Constantin

Vampire Pig
Joined
May 19, 2017
Messages
527
Thanks
158
#60
Fwiw, I have a bug tracker in with the development team re my LAGG not detecting that the primary LAGG interface is not working. Interestingly, they told me that building a failover with LACP will be far more robust than LAGG at detecting issues (assuming your switch supports LACP, of course).

Once I send them the FreeNas’ debug info, they likely will pinpoint the cause quickly.
 
Top