Orbi Cable Modem DHCP Issues

[matthewtshaver]

Hey everyone, we just installed an Orbi Cable Modem here in the past week.  Allow me to share my setup with you all.  

ISP:  Comcast (no issue)

CableModem: Orbi CBR40 - Firmware: V2.1.4.6_1.0.8 (In router mode)  with one Satellite Connected: 1 Wireless

1000 Nonmanaged Switch Connection to the CBR40

Orbi RBR connected via Ethernet in AP Mode - Firmware: V2.1.4.16 with one connected Satellite Wireless. 

Here's the issue:  The CBR is routing traffic / supping DHCP address to about 30-35 devices within our home.  When devices leave the network such as iPhones, or devices fall asleep such as Macs, when they attempt to get reconnect via WiFi, they have issues negotiating an address.  Upon looking at the DHCP table, the devices are "active" and did not fall off the list.  Inspecting the DHCP serving page, I do not see a lease time available?  Is anyone else having issues.  This does not happen to hard wired devices, only WiFi devices and they are not happening to just one iOS device it is all devices running iOS11.x, and I'm an app developer so I'm running iOS Dev 12.  Thoughts?

[FURRYe38]

Have you tried setting IP address reservations on your devices that sleep or go away and come back to the system? 

[vkdelta]

What are total Number of the Orbis you have in your setup? 

CBR40 - Orbi Cable Router

RBS20 - Satellite that came in CBK40 Kit

Do you have another RBR50 connected in the setup in AP mode?  

[matthewtshaver]

Still having the issues.  It does not seem to be on the devices that are wired but often those that are wireless.  We have the follwoing Orbi mesh system in a 4000 sq foot home.  

Orbi Cable Modem: CBR40 (This device is in router mode)

Orbi Satellite: RBS20 connected wirelessly to the CBR40

Orbi Router: RBR50 (This device is in bridge mode) connected via ethernet to the CBR40

Orbi Satellite: RBS50 connected wirelessly to the RBR50

Per Netgear's support tech, I have binded the RBR50 (after putting it in bridge mode) to the the CBR40.  I have additionally reserved the oast octet x.x.x.21 to my iPhone to test it.  I'm still at my original issue:

Here's the issue:  The CBR is routing traffic / supping DHCP address to about 30-35 devices within our home.  When devices leave the network such as iPhones, or devices fall asleep such as Macs, when they attempt to get reconnect via WiFi, they have issues negotiating an address.  Upon looking at the DHCP table, the devices are "active" and did not fall off the list.  Inspecting the DHCP serving page, I do not see a lease time available?  Is anyone else having issues.  This does not happen to hard wired devices, only WiFi devices and they are not happening to just one iOS device it is all devices running iOS11.x, and I'm an app developer so I'm running iOS Dev 12.

[FURRYe38]

Does the CBK40 system work with out the RBR50 system being connected and turned ON? Just the cable gatway and 1 or 2 satellites connected to the CBR40?

Whats the size of your home? SqFt?

[vkdelta]

Is your SSID for CBK40 and RBK50 system same?

Since they are two distinct system, they will not operate in same "mesh domain" (for the lack better terminology) and it might be creating problems. 

CBR40 is the primary DHCP server in the network. Although it might be aware of L3 information from devices, it wont have information about L2/L1 (roaming, wifi, etc) and it will would treat them as wired devices coming off RBR50.

One suggestion is to:

Make a network with CBR40, RBS20 and RBS50 and sync them together (Remove any RBR50 off the network)

[matthewtshaver]

The house, as stated above, is 4000 sq. feet.  When setting up the system, I was on the phone with Tech Support for quite a lengthy amount of time.  I am not a network newbie, as I have a network certification from Cisco...so this is nothing too hard to achieve.  After setting up the Orbi Cable Modem, I want to bind (via an Ethernet backhaul (really a backbone)) the RBR50 to allow a strong signal throughout the home.  According to the tech, she had me hand type the name of the network into the RBR50, so it will only (by the way as advertised) announce one single SSID not two.  

Today, I walk home with my iPhone...and the Orbi Cable Modem has to stutter when assigning an IP address though I have my iPhone reserved.  I have the 2.4 channel at 11, 5 at 26.  This all has to do with the Orbi Cable Modem and DHCP discovery - plain and simple.  I walk into our home, my iPhone should auto join the one and only broadcasted SSID, yet it does not.  When I go to iPhone settings, it sees the SSID but reports no Internet connectivity.  I have to log into the CBR40, and check to see is this a Comcast cable issue, or a Netgear software issue.  It's neither, and the logs are not explicit enough to know exactly what is happening.  

I'm about ready to disable the routing feature of the CBR40 and make it a cable modem only (bridge mode), and allow the RBR50 to route and transmit the SSID.  I cannot tell what is going on but previously the CBR40 was doing all my routing while the Comcast modem was providing Internet.  This was supposed to be easy...it's not!  Netgear sells Orbi as an expandable unit...and they really don't play well together.  Thoughts?

[FURRYe38]

The CBR40 is ment to be either a cable modem/router gateway combo unit or a cablem modem only (bridge mode). If your wanting to use the RBR50 with the CBR40 system, then it's probaby best to run the CBR40 in bridge mode and use the RBR50 series in router mode. The CBK40 is meant to be a stand alone Cable modem/MESH system that you can add RBS model satellites if needed, you can't add RBR units has they are ment to be there own wifi router and stand along wireless AP system with out the cable modem. If you already have a RBR or RBK system, I would recommend that you return the CBK40 system and use just the RBR system has or router and wifif MESH system. For a cable modem, use a stand alone CM700 cable modem for your ISP service interface and connect the RBR system to the modem. Then you'll have a good single NAT configuration and good wifi MESH system. The CM700 is the same cable modem built in to the CBR40 base unit.

I have a 5000sq ft home and use the CBK40 as my cable modem gateway and just 1 satellite 40 feet away from the base. I have great coverate and performance with just the base and 1 satellite. No need for any additional satellites. 

I set up my friends RBK50 system about a month ago, he likes his:

https://community.netgear.com/t5/Orbi/Orbi-firmware-update-v2-1-4-16-availability/m-p/1592753/highli...

Arrid cable modem in bridge mode and just the Orib system connected to it. 

This is easy, however Lets keep it simple and not make it hard and complex. 

---

@matthewtshaver wrote:

The house, as stated above, is 4000 sq. feet.  When setting up the system, I was on the phone with Tech Support for quite a lengthy amount of time.  I am not a network newbie, as I have a network certification from Cisco...so this is nothing too hard to achieve.  After setting up the Orbi Cable Modem, I want to bind (via an Ethernet backhaul (really a backbone)) the RBR50 to allow a strong signal throughout the home.  According to the tech, she had me hand type the name of the network into the RBR50, so it will only (by the way as advertised) announce one single SSID not two.  

Today, I walk home with my iPhone...and the Orbi Cable Modem has to stutter when assigning an IP address though I have my iPhone reserved.  I have the 2.4 channel at 11, 5 at 26.  This all has to do with the Orbi Cable Modem and DHCP discovery - plain and simple.  I walk into our home, my iPhone should auto join the one and only broadcasted SSID, yet it does not.  When I go to iPhone settings, it sees the SSID but reports no Internet connectivity.  I have to log into the CBR40, and check to see is this a Comcast cable issue, or a Netgear software issue.  It's neither, and the logs are not explicit enough to know exactly what is happening.  

I'm about ready to disable the routing feature of the CBR40 and make it a cable modem only (bridge mode), and allow the RBR50 to route and transmit the SSID.  I cannot tell what is going on but previously the CBR40 was doing all my routing while the Comcast modem was providing Internet.  This was supposed to be easy...it's not!  Netgear sells Orbi as an expandable unit...and they really don't play well together.  Thoughts?

---

[matthewtshaver]

I'd like to keep it simple but we purchases the CBK40 system after the RBR50 system and that is quite an investment into our home at this point. Though we have BestBuy Geek Squad on the two seperate system, I'm curious if we were to take back the RBR50, get two additional satellites and call it a day by binding them onto the CBK40.  Thoughts?

By the way, we never had an issue with DHCP / Internet connectivtiy utnil we introduced the CBK40 into the mesh.  I'm open to simple and just adding two satellites upstairs.  

[FURRYe38]

So heres the deal, if you keep the CBK40, then this will be your ISP modem and main host router, you can add satellites where needed. You would need to return the RBR50 system as the RBR50 can not work as a satellite. 

If you keep the RBR50 system, then this would be your main host router, however you would need an ISP modem to interface with there service. Something like a NG CM700 modem only. You can add satellites where needed. You would need to return the CBK40 system as the CBR40 can not work as a satellite. 

I would say either way, the base and no more than two satellites places at 30 feet or more should suffice for your home. I would try the base and just 1 satellite. 

Good Luck. 

[matthewtshaver]

First off...It is not a DHCP issue as I previously thought.   It is a DNS issue.  I know this because the router itself is having DNS issues as the DNS it is supplying is it's own address: 192.168.1.1.  It coughs up a furball on the LAN side which originally I thought was a DNS issue.  Here's my plan:

1.  Put the CBK40 Cable Modem into bridge mode.

2.  Make the RBR50 broadcast an SSID and route the traffic.

3.  Bind the two remaning sattelites to the RBR50 as they are upstairs and close to the RBR50.  

The RBR50 never has been the issue, it is the CBK40 Cable Modem that when introduced into the network mesh has caused issues.  I see no reason why I cannot use the CBK40 as a cable modem only, and the RBR50 as a DHCP serving unit / router and SSID broadcaster with the two satellites connected.

Thoughts?

[FURRYe38]

Are you using any custom DNS addresses ON the CBR40? Or letting it auto detect DNS from the ISP?

I use the following and have no DNS issues:

1.1.1.1 and 9.9.9.9

Yes the DNS that will appear on each connected device will be the routers IP address. NG doesn't support disabling of DNS relay so this is always ON.

Yes you can use the CBR in bridge modem mode. This should disable the wireless MESH and DHCP on the CBR40 and turn it into a modem only device. I haven't tryied this yet.