ISSUE with multiple RT-AC87x as APs

[phloid01]

I have a couple RT-AC87x's running as APs .. connecting directly to a layer 2 switch, servicing about 10-40 wireless devices (iPhones, androids, macbooks, dells, etc.) .... the issue is MASSIVE TCP retransmission traffic (like it fills up the network bandwidth, and actually slows/stops connections for 2-4 minutes) when one of two things happen:
- we reconfigure one of the devices (this is 169.x.x.x traffic, which seems to just be exchanged with the ASUS devices .. verified that it was their MAC addresses)
- an mobile device (most of the time, apple devices) leaves the network (when someone closes their laptop, and just leaves, or when the iPhone/Android/tablet leave the wifi range)

The traffic starts up sometime between a few seconds and a couple minutes, and often floods the network so bad, that AP's seem to reset themselves.

Each AP is on a manual IP address .. we use the same SSID for the devices (as that is what we should be able to do, that is why you use them as APs) .. we have them on separate channels, and have culled them down to 20Mhz and 40Mhz for the 2.4 and 5, respectively
we have also tried to shut down the 5 completeley
we have also tried shutting down the radios on one of the devices, but the TCP retransmissions still happen (weird)

Help! as these devices are nearly unusable in the designed and expected state ....
they were originally supposed to be setup to connect to another 87, which would act as the router, but that didn't work either.

 

[RMerlin]

Try capturing that traffic to determine what ports are being used (and if possible what type of traffic it is). That will help to pinpoint the problem.

One thing I would do is switch the router back to Router mode, then make sure to disable servies such as the Media Server, iTunes Server, etc... After that, switch back to AP mode.

Another thing that might be creating issues (in theory) is the fact that, internally, the RT-AC87U uses a 169.x.y.z network segment for communication between the Broadcom CPU and the Quantenna CPU. I'm not sure what type of effects it could have on your LAN, especially if you use the same subnet, or a conflicting subnet mask.

 

[phloid01]

still trying to figure out multiple RT-AC87U's as AP's

thanks for the reply ..
This happens after we make any changes on the routers, and apply them. Then 10-30 seconds later, it begins.
It looks like port 1007 is the source, and 815 is the destination ... i have attached the beginning (with the first ACK attempt, and then the beginning of the flood)
It pretty much goes on for about 100MB of traffic after that, in just a matter of seconds, and keeps that up for about 1-2 minutes ... the two IP addresses are the 169's .. and the MAC addresses are the MAC addresses for the ASUS devices.
The client these are at doesn't use that network address range for anything, and they use 10.0.0.0/8 as their internal network (yea, not optimal, but we inherited this mess).
The flood basically makes all network services run really slow for a couple minutes.
Side notes ... already shut down all of the unused services in router mode, then switched to AP mode ... even tried the AP config in router mode. We have also attempted shutting off the 5Mhz radios, and only going 2.4 ... but it still does it.
this is fascinating .. and I just don't know what is doing it.
When we pull the 87's out of the equation, and put the old wifi access points (old Cisco's) in their place, it all works fine ... just slow, as they are a/b/g only.

 

[RMerlin]

Port 815 is used by Apple, so maybe this is related to mDNS/Bonjour broadcasts.

 

[SpacemanJT]

Same here

Hi,

I previously posted about the same problem:
http://www.smallnetbuilder.com/forums/showthread.php?t=20282

I never got this fixed and my RT-AC87U is now gathering dust.

I tried all sort of configurations, including setting up new SSIDs and having NO clients connected, and I still got the random re-transmission issue, especially late at night.

I can well imagine that some sort of passing broadcast traffic is driving the RT-AC87U nuts, but I've tried it as an AP in both AP and Router mode, will every setting turned off as much as possible, to dumb the unit down, and I couldn't solve it.

I think there are some fundamental flaws in the firmware and I'm waiting for a new version that finally fixes something. Not holding my breath any longer though.

 

[SpacemanJT]

Phloid01, what devices do you have on your LAN?

Please let me know if you have any of the following to see if we have something in common:
Draytek Router
Thecus NAS
Sky HD+ Box
Freenas
Intel AMT - Q87, Q77 VPro
HP Switches - 1810-24G V2
DLINK Switches
HP 6127 Deskjet
HP 6980 Deskjet
Slingbox

Thanks,

Andrew

 

[phloid01]

Hey Andrew ... the only devices we have on that list is DLink switches ... several of them (24 and 48 port variety)... all layer 2 only.

The network is totally flat, but even when I tried to use one of the 87's as a router, the traffic on the 87's still was insane when one was acting as an AP....

OMG!!!

I guess nobody is trying to use these in a corporate network.
I have one at home, and it seems to be fine.
But they definitely occasionally kill the network bandwidth with their strange broadcast and TCP retransmission traffic .... I have chatted, and called the support guys, and all they say is to have each AP use a dedicated IP address, and a dedicated/unique SSID, which would mean multiple SSID's for the same corporate network ...
How'bout no!

I'm hoping an updated firmware will come, but as SpacemanJT said ... I'm not holding my breath .... We will probably end up just putting these in small home offices, and purchasing something else.

As of now !!!!! I cannot recommend these for anything except stand-alone, small home offices.

 

[shad0wz]

You are not the only one with this issue.
I too am seeing exactly what you're seeing.

Two RT-AC87U's attached to same switch in AP mode wipe out my entire network. As soon as one of the RT-AC87U's are unplugged this condition (storm) disappears.

If I stick the two RT-AC87U's on different VLANS's the problem goes away.
Something is amiss with these units.
Ive tried latest official and latest beta firmware's.

They are connecting to a cisco SG500X-24P which then connects to a sonicwall NSA2600.

Sonicwall doing all routing and dhcp. Cisco doing layer2.

Wireless clients consist of xbox one's xbox 360's ipads, iphones, laptop's (pc and apple) android tablets, chromebox... u name it.

A Qnap 1079 is sitting off the cisco SG500x via two 10G interfaces offering plex services to a variety of plex clients

 

[phloid01]

Hey Shad0wz .. it is interesting, even if you turn off the radios, the still blast the network every hour or so. It is just one of the strangest things. I have captured a bunch of traffic with WireShark, and it just suddenly blows up the network. I can't even have them as AP's from another 87 as a router. The AP function is just not functional.
I'm really disappointed. I had such high hopes, and was really looking forward to calling this done.

Anyone else figure this out?

and I wish ASUS Support had anything other than crickets for me?

Sometimes it is 169. traffic (from the MAC addresses of the 87's)
Sometimes it is TCP Retrans loop, which eventually (after 2-4 minutes) kills itself, but not until the network is completely flooded

If I take these devices out .. all is fine.

 

[phloid01]

Port 815 is used by Apple, so maybe this is related to mDNS/Bonjour broadcasts.

Thanks RMerlin ... this is actually an additional issue we are seeing with these ASUS RT-AC87's in AP mode ... sometimes the multicast traffic just goes insane between them, and if they are connected as AP's onto layer 2 switches, the traffic goes bonkers for a couple minutes.

Just one of the many issues these devices have when running in AP mode.

I do hope that ASUS comes out with a firmware fix for AP mode ... right now, we are evaluating other devices, in order to replace these at the client sites.

 

[shad0wz]

Im ready to give up on these routers / ap's as well. Looking at the new AC3200's but thats beyond the scope of this thread... Am really interested hearing from others with two of these bad boys on the same L2 switch / vlan.

Ive had one of the AP's up all weekend long, working fine... throw in the second ap and boom... explodes in 10mins

 

[afh3]

Yep. +1 and all that.

I've had two AC87R units in AP mode since I bought them in September, and at least 3-5 times a week one of them will suddenly go nuts and jam the entire network with traffic. Pretty much kills everything on the network at that point (no pun intended.)

Happened again today, just an hour ago.

Solution is always the same. Power-cycle the unit with the LAN-light that is blinking so fast that it basically looks like it is half-lit. After that, it's all good - for anywhere from a couple hours to a day or two.

I've reset them. I've re-flashed them. I've run Merlin F/W. I've had them exorcised. (Well, OK, I lied. The guy refused to do that once he found out that it was a Wi-Fi access-point.)

As long as both are active at the same time, the LAN-storm will happen within 48 hours. Sometimes much less.

Good (?) to know that I'm not alone on this one.

My old 66R units were also in AP-mode, and on the same LAN, with the same cabling, with the same router, with the same breakfast-nook furniture, and this didn't occur even once in the two years I had them.

Shouldn't have sold them off so soon, I guess.

Oh, well.

What's $600 bucks in the grand scheme of things, anyway?

 

[phloid01]

UPDATE -- ASUS SUPPORT FOR OVER AN HOUR (AGAIN)

So .. after yet another marathon episode with the ASUS support guys ... here is the most recent info I got, after a very long conversation ....

Me saying:
- Let me see if I got this right, from what you are telling me ... To use these RT-AC87U's as Access Points, I must --
1) connect them to a router directly
2) have this router also dole out dynamic IP addresses to these access points
3) then also have the router, not just route the traffic, but actually NAT the traffic sourced from the LAN side of the router (instead of just routing it).
4) (maybe) also make sure to have each of the AP's be assigned a dedicated SSID
5) (maybe) also assign a dedicated communication channel to each radio

from Steven T., at ASUS Support
That will be the most stable configuration, yes.

So .. in another words, these cannot be used as Access Points, in the true meaning of an AP ... they must be configured specially.

The reason I was given was .. these are not Commercial Grade, they are Consumer Grade ... when I asked for the documentation of the differences, he said I would probably not be able to find this ... but if he had to write it, that is what he would write ......

So, basically .. if you want these to be Access Points .. just go buy another product .. because they apparently can only be AP's if they are acting in "Access Point Mode", and get a dynamic IP address from another router, and that router is also NAT'ing the traffic (instead of just routing it).

As you can guess .. I'm VERY DISAPPOINTED, and will not be purchasing any ASUS products again, as this experience has left me VERY UNSATISFIED as a Consumer Grade person.

 

[shad0wz]

Wow... looks like these will be the last Asus AP's / wifi routers Ill be buying.
Anyone want to buy a couple RT-AC87U's on the cheap? LOL

 

[arachnida]

Hello,

I'm new here. I've bought two 87U, one as my router/DHCP/FireWall/no WIFI and the second one as an AP. I seem to be running into the same problems as you are having, network gets flooded and my IP cams can't transport the images to my NAS anymore. My cameras get disconnected about once per 4h. Also my music streaming from my NAS is interrupted.

I see al lot of "kernel: br0: received packet on vlan1 with own address as source address" messages in the log of both routers.

On my LAN: Synology NAS, SonoS, Mobotix, Apple iDevices, NEST, LIFX...

Do you advise me to bring the product back to the shop as it seems from what I've read on several forums there is no solution to this problem?

I also noticed my LAN MAC addresses are the same as the 2.4GHz addresses on both routers, 5GHz is different. Is this a bug?

Cheers from Belgium,
arachnida

 

[shad0wz]

Good Day all,

SO I bit the bullet... tired of waiting on Asus to fix these things.

Have replaced both my asus RT-AC87U's with two Netgear R8000's.
They have been up and running perfectly all weekend long. Having both my AP's up without a single issue was a refreshing change.

I really hope Asus brings a fix for all those that are still using the rt-ac87's

All the best!

 

[arachnida]

Disappointed by Asus.

I've disabled both WLAN networks during the night, no more problems. Now I have an expensive switch.

Will try the latest stable Merlin I could find, RT-AC87U_3.0.0.4_376.48_1. If this doesn't help the routers go back to the shop.

Are companies really thinking we all like to do the beta testing for them? The last years it seems they really do think so! Nest, Asus, Parrot, DJI to name a few. I don't mind being a beta tester if I want to, like for SonoS, Pebble and the like but not for critical devices were my security cameras depend on or the heating of my house. Aaaah....

EDIT: Although I like the additional magic of the Merlin Update the problem stays the same. When it happens the mP time of my internet router goes to 100%. Rebooting the AP router makes it drop immediatly back to a normal value.

 

[arachnida]

I just received an answer from ASUS support:

The message in combination with the problem that you notice with the RT-AC87U indicates a problem that is known.

This problem would occur less when no product/switch is attached to LAN 1.

Currently our R&D department is investigating this problem.
Where a new firmware version should solve this in the future.

 

[phloid01]

finally an answer from ASUS support that acknowledges that this is B/S!!!!!

now lets see if they fix it ..... in the meantime, I'm going to probably bite the bullet too and go to another manufacturer .... I guess it is a write-off

ASUS (and I know this isn't an ASUS supported forum, but I have to plead anyway)..... Please do not do this again to your customers. I know and understand the need to get product to the market fast and first, but always, always, always make sure the fundamental networking functions of the advertised device are fully functional.