Orbi RBR40/RBS40 (V2.1.4.16) mesh network drops connection to Apple iMac

[rayterry]

I have an ongoing issue where my Orbi RBR40/RBS40 (firmware = 2.1.4.16) mesh network drops the connection to an Apple iMac on OSX v10.13.5. No issues like this previously with my old Apple Time Capsule and D-Link AC1200 Wi-Fi Gigabit Range Extender(DAP-1650).  The iMac itself shows it as connected to the mesh network (via the radio wave icon in the top right icon bar), but checking the connected devices via my iPhone does not show the iMac and a few other devices as connected to either the router or the satellite. If I turn off wifi on the iMac and then turn it back on again it shows that 10.0.1.99 (I have it nailed to that ip addr) is connected to the router and is on the 5ghz channel. The iMac and the router are only about 20 feet apart. When connected the Orbi app shows the iMac is connected at full strength. I've tried changing the 2.4ghz from channel 8 to 11 (didn't think that would make a diff and it didn't). The 5ghz channel is set at the highest possible, 48. I've rebooted the iMac. Every few hours the router just loses connection to the iMac. Two other Macs (same OSX rev) are within 9 ft of the iMac and they never experience this issue. When it is dropped off the net a Lanscan from the iMac shows nothing but the iMac on 10.0.1.99. That makes sense. Any ideas how to keep the mesh network from dropping the connection to the iMac?  This iMac hosts my security camera system.  I submitted a support ticket to Netgear on 6/14 ago re this and they have yet to respond.  It looks like this  problem has been around for ever.  No fix yet for it?  Thx.

[rayterry · Accepted solution]

The changes that apparently fixed my connection issue...

In orbilogin.com, Advanced Wireless Settings both 2.4GHz and 5GHz changed CTS/RTS Threshold to 2307.

In orbilogin.com, Advanced WAN Setup changed MTU Size(in bytes) to 1492.

Powered down the Orbi.  Powered down the cable modem.  Restarted both.

[FURRYe38]

Any other wifi neighbors near by? If so, how many?
What channels are you using? Try manual channels 1, 6 or 11 on 2.4Ghz and other unused channels on 5Ghz.

Disable MIMO, Daisy Chain and Fast Roaming.

Whats the distances between the router and satellites.
Whats the distances between the router, satellite and TV?

What is the Mfr and model# of the ISP modem the Orbi is connected too? Built in router here by chance?

[rayterry]

Yes, there are many neighbors.  Istumbler shows other routers on chan 11.  I've tired other chans, but 11 shows no other routers with strong signals.  Also on chan 48 with no other routers showing up.  MIMO, Daisy Chain and Fast Roaming are disabled.  Distance between router and sat is ~60 feet and one floor apart.  Router and tv are 2 ft apart.  The cable modem is a Netgear Nighthawk AC1900 (24x8) DOCSIS 3.0.

[FURRYe38]

Try channels 1 or 6 if there are none or few other wifi neighbors there.

Is this the modem you have?

Also I would try shortening the distance between the router and satellites as a test. 60feet maybe on the outer finges of keeping too signal between the router and satellite...try 40 to 50 feet and test...

https://www.netgear.com/support/product/C7000.aspx

If so, Couple of options,
1. Configure the modem for transparent bridge mode. Then use the Orbi router in router mode.
2. If you can't bridge the modem, disable ALL wifi radios on the modem, configure the modems DMZ for the IP address the Orbi router gets from the modem. Then you can use the Orbi router in Router mode.
3. Or disable all wifi radios on the modem and connect the Orbi router to the modem, LAN to LAN and configure AP mode on the Orbi router. 

[rayterry]

This is the Netgear cable modem that I'm using;

https://www.netgear.com/home/products/networking/cable-modems-routers/C7100V.aspx

Looks like no new firmware updates are available for the modem.

I tried using chan 1 and 6, but iStumbler shows a lot of strong signals from neighbors on those chans and perf was super slow so I switched to the least used chan which is 11.  Perf is still slow, but...

I used a tape mearsure to check the distance between router and sat.  One floor and ~35 feet apart.  I also had it in a different room upstairs, but had the same issue there.  No other places upstairs to put it.

[rayterry]

P.S.  Forgot to mention that this issue occurs from once every other day to 3 times a day.

[FURRYe38]

Is the modem in bridge mode? That modem has a router built in and I would get the modem in bridge mode if possible...disable ALL wireless radios on the modem as well...

[rayterry]

I do not believe the cable modem is in bridge mode.  When I follow the c7100v user manual directions and attempt to login to the modem to do that I seem to be talking to the Orbi instead.  i.e. routerlogin.com/net is same gui and data displayed as with orbilogin.com/net.  I'll keep looking or maybe I can get Netgear support to answer that question.  Still no response from support on this wifi dropping problem that I submitted to them a few weeks ago.

[FURRYe38]

Try changing to manual channels 1, 6 ro 11 and disable Daisy Chain, MIMO and Fast roaming on the router and see if this help with the iMac. I have an iMac, 2008-9 era. It connects to satellite in next room over. Haven't seen any issues...

[rayterry]

Thanks.  Those setting are disabled and I've gone from 1 to 6 to 11.  11 seems to be working the best thus far as there are no strong chan 11 signals nearby.  Re Macs, I have 3 in the same room and only 1, the iMac, has the issue (others are a Macbook Pro and a Mini).  I guess it could be a problem with the iMac, but there were no issues like this when I using the Time Capsule.  So why did I switch you may ask...  TCs have been discontinued by Apple, but you probably know that already.  Thx for your ideas...

[FURRYe38]

Can you lan wire connect the one iMac and see if it does anything different? 

[rayterry]

Yes, I have cables long enough to try that.  I'd just have to walk over a lan cable across the living room for 5 or 6 days to see if things would be better, and I suspect they would.  I'm trying chan 6 again, just for grins, so maybe after that test completes.  Thx again for trying to help.

[rayterry]

Well, that didn't take too long.  The chan 6 test ended as before... with a hung wifi connection.  😞 

[rayterry]

The iMac in question is always connecting via the 5g link. Is there a way to force it to connect via the 2.4g?

[FURRYe38]

You could try lowering the power output of the 5Ghz radio from 100% to 50% persent and see if this helps any. 

 As a last resort, I would do a full factory ERASE on the router and satellite. THen set up from scratch. I would test with out the satellite added initially. See if the problem continues. 

[rayterry]

Tried 50% and 75% power, but no diff.  Called support and they said to change cts on 2.4 and 5 to 2307 and change mtu to 1492 and restart.  Did that, now waiting to see what happens.

[FURRYe38]

Keep us posted...

[rayterry]

Fingers are crossed as I write this, and that isn't easy to do...

It looks like that might have fixed the issue.  I admit that I read about that change/fix in a related thread, but the following comments said that moding those 3 parms made no sense and wouldn't help.  I should have igmored that.  It has been over a day now since this problem occurred.  Another couple days of stability will indicate to me that this issue is over.  Thx much for your help.

[FURRYe38]

Good to hear.

Come back if you need. Enjoy.

[rayterry · Accepted solution]

The changes that apparently fixed my connection issue...

In orbilogin.com, Advanced Wireless Settings both 2.4GHz and 5GHz changed CTS/RTS Threshold to 2307.

In orbilogin.com, Advanced WAN Setup changed MTU Size(in bytes) to 1492.

Powered down the Orbi.  Powered down the cable modem.  Restarted both.

[FURRYe38]

Awesome. Thanks for letting us know. Will keep this in mind.

Enjoy.