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Repeated Internet loss: Cause = public IP/MAC being used on LAN!

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Repeated Internet loss: Cause = public IP/MAC being used on LAN!

I keep losing Internet access.  Narrowed dow the problem to Xfinity or Netgreat ARP issue.

 

My C7000 cable modem sometimes uses it's public IP and MAC address on the LAN.

 

Internet: 98.xxx.xxx.95, a0:04:60:x:xx:c9

LAN: 172.16.0.1, 255.255.255.255, a0:04:60:xx:xx:ca

 

11:54:29.355222  In a0:04:60:xx:xx:ca > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 60: arp who-has 172.16.0.17 tell 172.16.0.1

11:54:30.778173  In a0:04:60:xx:xx:c9 > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 60: arp who-has 172.16.0.2 tell 98.xxx.xxx.95

11:54:35.819975  In a0:04:60:xx:xx:c9 > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 60: arp who-has 172.16.0.2 tell 98.xxx.xxx.95

11:54:40.796601  In a0:04:60:xx:xx:c9 > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 60: arp who-has 172.16.0.2 tell 98.xxx.xxx.95

 

The first line shows it correctly using it's LAN IP (172.16.0.1) and MAC (a0:04:60:xx:xx:ca) when ARPing for a LAN device.

 

The other lines show it incorrectly using it's public IP (98.xxx.xxx.95) and MAC (a0:04:60:xx:xx:c9) when ARPing for 172.16.0.2.

 

C7000

Xfinity

Hardware 1.05

Firmware V1.01.33