Orbi wanting two public IP's via DHCP

[packetpusher]

Hello,   We are trying to help a customer that owns a ORBI router device.

When doing a packet capture on the PUBLIC facing interface from the ORBI we see that the ORBI wants two public IP's.

If we limit the number of public IP's that the ORBI can use, then the ORBI doesn't work.

Why does the ORBI need need multiple public IP's

How do we make sure the ORBI will operate with a SINGLE IPv4 Public IP  that is issued from us (the ISP) via DHCP

NetGear ORBI's are the only CPE on our network that we have this issue with.  

Note:

1. This is PUBLIC IP's, not RFC-1918 addresses on the internal or LAN side

2. This has NOTHING to do with DNS

3. NO We do NOT provide a router.  The customer is connected via a P2MP microwave system (not wifi) as a OSI Layer 2 link.

    Our aggregation router issues public IP's via DHCP

Thank you

[CrimpOn]

Please explain how the Orbi wants two public IP's.

It is common for devices to issue multiple DHCP requests, waiting for a response from some DHCP server.

This is the first time anyone has ever suggested an Orbi "wants" multiple IP addresses.

It would take some effort to replicate, but in the past I have captured the behavior of my Orbi performing a DHCP dialog with Spectrum.

Orbi DHCP's for an IP, gets an IP, and responds.  All is good.

[CrimpOn]

The Netgear Orbi can be configured in two modes: "router" and "Access Point" (AP).  As a router, the Orbi asks for a public IP address via DHCP, and then creates private IP addresses for every device attached to it, using Network Address Translation (NAT) to allow them to communicate with the internet.  When in AP mode, the Orbi requests an IP address using DHCP, and passes the DHCP requests for every other device to the upstream router.

Perhaps the Orbi in question is in AP mode, rather than router mode?  That would lead to multiple DHCP requests from different MAC addresses.  This would not be tolerated well by most ISP networks.  (microwave or not).

[FURRYe38]

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

Any Orbi our single NAT router only gets/requires 1 IP address from any kind of DHCP service, WAN or LAN. Orbi AC doesn't support LAG either. Orbi AX does where you could have two WAN IP addresses aging to the RBR. 

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@packetpusher wrote:

Hello,   We are trying to help a customer that owns a ORBI router device.

When doing a packet capture on the PUBLIC facing interface from the ORBI we see that the ORBI wants two public IP's.

If we limit the number of public IP's that the ORBI can use, then the ORBI doesn't work.

Why does the ORBI need need multiple public IP's

How do we make sure the ORBI will operate with a SINGLE IPv4 Public IP  that is issued from us (the ISP) via DHCP

NetGear ORBI's are the only CPE on our network that we have this issue with.  

Note:

1. This is PUBLIC IP's, not RFC-1918 addresses on the internal or LAN side

2. This has NOTHING to do with DNS

3. NO We do NOT provide a router.  The customer is connected via a P2MP microwave system (not wifi) as a OSI Layer 2 link.

    Our aggregation router issues public IP's via DHCP

Thank you

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