Internet Drop due to DHCP Issue? (Two RT-N66U Routers)

[sweebez]

Hello! Every day, my Asus router randomly drops my internet connection, only to restart and reconnect a few minutes later (usually!).

The error I see is usually: "Internet status: Your ISP's DHCP does not function properly."

My Setup (Modem-->Router1--->Router2):

• ISP: Wide Open West
• Modem: Arris DG3270A Cable Gateway Modem (in Bridge Mode, so WiFi and DHCP should be off)
• Router 1: Asus RT-N66U Wireless Router (Device Name: "RT-N66U-Library"), in default Wireless router mode
• Router 2: Asus RT-N66U Wireless Router (Device Name: "RT-N66U-Kitchen"), in Access Point(AP) mode
• Router Firmware: Asuswrt-Merlin v 380.66_4.

I already tried the Original Asus, Updated Asus, and Merlin v 380.66_4 firmware versions, and I already replaced the modem.

I'm not sure if you have any ideas how to approach this issue, but if you have any leads, I would be extremely grateful -- and I'll provide whatever info you'd like! Thank you very much for your time .

After today's dropped connection, I saved this System Log (from RT-N66U-Library):

Jun  8 14:00:41 disk_monitor: Got SIGALRM...
Jun  8 20:42:09 WAN Connection: Ethernet link up.
Jun  8 20:42:09 rc_service: wanduck 1138:notify_rc restart_wan_if 0
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: Failed to get IP for interface eth0
Jun  8 20:42:09 miniupnpd[1237]: SendNATPMPPublicAddressChangeNotification: cannot get public IP address, stopping
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:09 kernel: Attempt to kill tasklet from interrupt
Jun  8 20:42:11 wan: mac clone: [wan0_hwaddr] == [E0:94:67:2C:0C:D6]
Jun  8 20:42:17 miniupnpd[1237]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:17 WAN Connection: ISP's DHCP did not function properly.
Jun  8 20:42:18 rc_service: udhcpc 7770:notify_rc start_firewall
Jun  8 20:42:18 miniupnpd[1237]: shutting down MiniUPnPd
Jun  8 20:42:18 start_nat_rules: apply the nat_rules(/tmp/nat_rules_eth0_eth0)!
Jun  8 20:42:18 wan: finish adding multi routes
Jun  8 20:42:18 miniupnpd[7806]: HTTP listening on port 52609
Jun  8 20:42:18 miniupnpd[7806]: Listening for NAT-PMP/PCP traffic on port 5351
Jun  8 20:42:18 rc_service: udhcpc 7770:notify_rc stop_upnp
Jun  8 20:42:18 rc_service: udhcpc 7770:notify_rc start_upnp
Jun  8 20:42:18 rc_service: waitting "stop_upnp" via udhcpc ...
Jun  8 20:42:18 miniupnpd[7806]: shutting down MiniUPnPd
Jun  8 20:42:20 dhcp client: bound 192.168.100.21 via 0.0.0.0 during 20 seconds.
Jun  8 20:42:20 miniupnpd[7810]: HTTP listening on port 45534
Jun  8 20:42:20 miniupnpd[7810]: Listening for NAT-PMP/PCP traffic on port 5351
Jun  8 20:42:22 WAN Connection: WAN was restored.
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: Failed to get IP for interface eth0
Jun  8 20:42:37 miniupnpd[7810]: SendNATPMPPublicAddressChangeNotification: cannot get public IP address, stopping
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 miniupnpd[7810]: ioctl(s, SIOCGIFADDR, ...): Cannot assign requested address
Jun  8 20:42:37 WAN Connection: ISP's DHCP did not function properly.
Jun  8 20:42:37 stop_nat_rules: apply the redirect_rules!
Jun  8 20:42:57 WAN Connection: Ethernet link up.
Jun  8 20:42:57 rc_service: wanduck 1138:notify_rc restart_wan_if 0
Jun  8 20:42:57 kernel: Attempt to kill tasklet from interrupt
Jun  8 20:42:59 wan: mac clone: [wan0_hwaddr] == [E0:94:67:2C:0C:D6]
Jun  8 20:43:00 rc_service: udhcpc 7831:notify_rc start_firewall
Jun  8 20:43:00 miniupnpd[7810]: shutting down MiniUPnPd
Jun  8 20:43:00 start_nat_rules: apply the nat_rules(/tmp/nat_rules_eth0_eth0)!
Jun  8 20:43:00 wan: finish adding multi routes
Jun  8 20:43:00 miniupnpd[7871]: HTTP listening on port 43347
Jun  8 20:43:00 miniupnpd[7871]: Listening for NAT-PMP/PCP traffic on port 5351
Jun  8 20:43:00 rc_service: udhcpc 7831:notify_rc stop_upnp
Jun  8 20:43:00 rc_service: udhcpc 7831:notify_rc start_upnp
Jun  8 20:43:00 rc_service: waitting "stop_upnp" via udhcpc ...
Jun  8 20:43:00 miniupnpd[7871]: shutting down MiniUPnPd
Jun  8 20:43:01 dhcp client: bound 50.4.67.161 via 50.4.64.1 during 62644 seconds.
Jun  8 20:43:01 miniupnpd[7875]: HTTP listening on port 57694
Jun  8 20:43:01 miniupnpd[7875]: Listening for NAT-PMP/PCP traffic on port 5351
Jun  8 20:43:02 WAN Connection: WAN was restored.
Jun  8 20:43:14 rc_service: httpd 1232:notify_rc start_autodet
Jun  8 20:43:18 rc_service: httpd 1232:notify_rc start_webs_update

 

[john9527]

I'm not sure if you have any ideas how to approach this issue

You have two 'Ethernet link up' messages without any corresponding link down messages. This is usually a bad/marginal cable or connector from the modem to router. Try replacing it with a good quality cat5e or cat6 cable.

 

[sweebez]

You have two 'Ethernet link up' messages without any corresponding link down messages. This is usually a bad/marginal cable or connector from the modem to router. Try replacing it with a good quality cat5e or cat6 cable.

Thank you! Done. Will bump if this does not resolve the issue.

 

[sweebez]

Bump: The issue reappeared this morning despite the new ethernet cable. Any new ideas?

Resolved: It was a signal/line issue with the ISP. Occam's razor wins again.