Slow Ethernet Connection between RBR 850, Mac, and Xfinity Gateway

[MontereyFred]

I’m having an issue with a wired ethernet connection. Here’s the background…

I have a Mac Mini M1 with a 1 Gbps ethernet port, a Netgear Orbi RBR850 router, and an Xfinity XB8 gateway with (3) 1Gbps ethernet ports and (1) 2.5 Gbps ethernet port. The router is in bridge mode with a 1.2 Gbps internet plan. I’m running Cat-6 cables throughout, none longer than 6 feet. All devices are updated to the current OS and firmware.

The problem is that, when the router is cabled into the 2.5 Gbps port on the gateway, the measured speed to the Mac’s ethernet port is in the 350 Mbps range. Nicely enough, the WiFi speeds to the Mac still run in the 850 Mbps to Gigabit range. Dashboards indicate that the wired connection between Mac and router is 1 Gbps.

Lots of other things are working right…WiFi to all my other devices (mostly Apple) is fine. When I plug the router into one of the Gigabit ports on the gateway, I understandably get near-Gigabit WiFi to all devices and a Gigabit ethernet connection all the way to the Mac. When I bypass the router and plug the Mac straight into the 2.5 Gbps port on the gateway, I also get the expected Gigabit Ethernet connection.

The wired connection to the Mac worked fine on the Xfinity gateway that I had just prior to the XB8. I can live with this, given the strong WiFi to the Mac, and perhaps a future update will fix things. At the same time, it’s leaving me a little perplexed. I’ve read many stories like mine but have found no solutions.

I’m told that the 2.5 Gbps port on the XB8 uses IPv6, and have tried both the “autoconfig” and “Use DHCP Server” settings in the IPv6/LAN Setup section on the router without joy.

Thoughts are welcome and thanks for listening…

[CrimpOn]

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@MontereyFred wrote:

I’m told that the 2.5 Gbps port on the XB8 uses IPv6, and have tried both the “autoconfig” and “Use DHCP Server” settings in the IPv6/LAN Setup section on the router without joy.

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Can you please check the Orbi WAN  connection and verify that it is getting an IPv4 address?

This would be on the web interface Advanced Tab in the box labelled Internet Port (upper right), or on the Orbi 'app' Router Settings on the Internet Port tab (External IP Address).

My understanding is that IPv6 would be in addition to IPv4 (not "instead of").

In what way does appear that IPv6 is "without joy"?  On the Orbi web interface, the Advanced Tab, Advanced Settings menu "IPv6" does  not display this information:

[CrimpOn]

Interesting that the Mac Mini M1 appears to have an Ethernet port capable of 10G:

https://support.apple.com/kb/SP823?locale=en_US 

It might be fun to see what speed the Mini reports when connected directly to the 2.5G port on the XB8 gateway.

Just an idle question: what speed does the Orbi Speed Test report when connected to the XB8 gateway?

You do not appear to be the only person reporting unusual behavior in terms of the 850 router 2.5G and 1G Ethernet ports.

[MontereyFred]

Thanks for your reply.  Yes, I show an IPv4 address and agree that it's not either v4 or v6.

I'm not quite grasping what you are asking re the IPv6 section but checking either the autoconfig or use DHCP boxes didn't make a difference in the wired connection speed...

[MontereyFred]

I hope I didn't confuse you but the ethernet port in my Mac is indeed 1 gig.  The 10 gig option came out quite a bit later.

I mentioned in my (admittedly long) note that I did connect the Mac directly to the 2.5 gig port in the gateway and got a 1 Gbps connection.  That's understandable because of the limit of the port on the Mac.

The Orbi speed test generally comes back around 1350 Mbps down and 250 up.

Yeah, I've seen multiple reports of similar issues but everyone is pretty much scratching their heads like me.  Thanks...

[CrimpOn]

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@MontereyFred wrote:

I hope I didn't confuse you but the ethernet port in my Mac is indeed 1 gig.  The 10 gig option came out quite a bit later.

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Thanks.  "My Bad" for searching the internet for Mac Mini M1 specs and believing what showed up.

I am totally confused by these reports about the 2.5G Ethernet port having "issues".  For at least a decade, consumer routers have had a four-port Ethernet module. These modules are essentially Ethernet switches which learn which MAC addresses can be reached on each port. (Even inexpensive switches have the ability to remember thousands of MAC addresses.)  So, when a packet arrives at one port and is addressed to a specific MAC address, the packet never leaves the switch module.  It comes in one port and goes out another port.  (This is one reason it is impossible to prevent devices connected to the same unmanaged switch from communicating with each other.)  I have a suspicion that the way Netgear merged a 2.5G Ethernet port with three 1G Ethernet ports is not "entirely right".

What is actually going on is a total mystery.

[MontereyFred]

My setup is a little different but this seems very similar to a problem I've been trying to sort out...

https://community.netgear.com/t5/Orbi-WIFI-6-AX-AND-Wi-Fi-6E-AXE/Slow-Ethernet-Connection-between-RB... 

[FURRYe38]

Your ISP Modem already has a built in router and wifi. This would be a double NAT (two router) condition which isn't recommended. https://kb.netgear.com/30186/What-is-Double-NAT
https://kb.netgear.com/30187/How-to-fix-issues-with-Double-NAT
Couple of options,
1. Configure the modem for transparent bridge or modem only mode. Then use the Orbi router in router mode. You'll need to contact the ISP for help and information in regards to the modem being bridged correctly.
2. If you can't bridge the modem, disable ALL wifi radios on the modem, configure the modems DMZ/ExposedHost or IP Pass-Through 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, configure AP mode on the Orbi router. https://kb.netgear.com/31218/How-do-I-configure-my-Orbi-router-to-act-as-an-access-point and https://www.youtube.com/watch?v=H7LOcJ8GdDo&app=desktop
Try option #2 first...Then try option#3 with the Orbi system. 

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@MontereyFred wrote:

I’m having an issue with a wired ethernet connection. Here’s the background…

I have a Mac Mini M1 with a 1 Gbps ethernet port, a Netgear Orbi RBR850 router, and an Xfinity XB8 gateway with (3) 1Gbps ethernet ports and (1) 2.5 Gbps ethernet port. The router is in bridge mode with a 1.2 Gbps internet plan. I’m running Cat-6 cables throughout, none longer than 6 feet. All devices are updated to the current OS and firmware.

The problem is that, when the router is cabled into the 2.5 Gbps port on the gateway, the measured speed to the Mac’s ethernet port is in the 350 Mbps range. Nicely enough, the WiFi speeds to the Mac still run in the 850 Mbps to Gigabit range. Dashboards indicate that the wired connection between Mac and router is 1 Gbps.

Lots of other things are working right…WiFi to all my other devices (mostly Apple) is fine. When I plug the router into one of the Gigabit ports on the gateway, I understandably get near-Gigabit WiFi to all devices and a Gigabit ethernet connection all the way to the Mac. When I bypass the router and plug the Mac straight into the 2.5 Gbps port on the gateway, I also get the expected Gigabit Ethernet connection.

The wired connection to the Mac worked fine on the Xfinity gateway that I had just prior to the XB8. I can live with this, given the strong WiFi to the Mac, and perhaps a future update will fix things. At the same time, it’s leaving me a little perplexed. I’ve read many stories like mine but have found no solutions.

I’m told that the 2.5 Gbps port on the XB8 uses IPv6, and have tried both the “autoconfig” and “Use DHCP Server” settings in the IPv6/LAN Setup section on the router without joy.

Thoughts are welcome and thanks for listening…

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[MontereyFred]

Thanks, I've been in bridge mode all along per the first paragraph of my note and only left it for a few minutes to see if the speeds improved.  They didn't.  I'm really not interested in using the Orbi in access point mode and would rather keep the Mac on WiFi until this gets properly sorted out...

[FURRYe38]

AP mode is just a test to see if speeds improve or not. You'll need to put the ISP modem in to router mode to check this. 

What FW version is loaded on the system? 

[MontereyFred]

Furry, FYI, I put the Orbi in AP mode and the Xfinity gateway in router mode, and found no appreciable change in speeds.  My Orbi firmware is at V7.2.6.21...

[FURRYe38]

You'll only see around 900Mpbs with ethernet connections behind the RBR due to the LAN ports only being 1000Mpbs. You not see anything over this. Yes the Orbi onboard speed test app is reporting seeing over this due to the RBR WAN port supports 2.5Gb connection rates. However the LAN ports are capped at 1000Mpbs. Nothing can change this. If you want to see ISP speeds over 1Gb across the WAN to LAN side, you'll need a different router system. Orbi 9 series and NH RS700 now sport 2.5 and 10Gb LAN ports along side the WAN port. 

[MontereyFred]

Yes, I understand all of that but that doesn't address the problem here.  When you strip away all of the background and troubleshooting results, the core issue is that my wired connection to my Mac is seeing internet speeds around 325 Mbps when connected to the Orbi and just under a gig when connected straight to the Xfinity XB8.  WiFi speeds aren't irregular at all.

This never happened with previous Xfinity gateways.  While I can't completely rule out other causes, the preponderance of information I have gathered leads me to believe that the Orbi and XB8 aren't playing well together...

[FURRYe38]

I would agree with all that. 

I would make contact with NG support and open a support ticket. 

I would enable debug logs on the routers IP address/debug.htm and select WAN/LAN packet capture and well and enable it. Then run some speed tests, x3. I would use the internal onboard RBR test, then use Ooklas installable speed test app on your wired Mac x3. Then save off the logs and send to NG.

https://my.netgear.com/support/contact.aspx
https://www.netgear.com/support/contact.aspx
Then clicking on "Get answers about NETGEAR products before I buy" then clicking on "Networking for Home" then "Chat with us".

[Wg197756]

I am experiencing the exact same problem with the same equipment. Only difference is 2gig tier speed from Xfinity. Using XB8 with 2.5g port on bridge mode and also Orbi 852. Will follow closely and current “solution” is to not use 2.5g port on XB8 and merely use one of the 3 available gig ports to realize at least better connected Ethernet speed.