dnsmasq-dhcp failure AC3100- any idea ?

[PIO1]

Hi -

Been running merlin on my Asus routers for a few years but lately I have come across an issue that I cannot find the root. At random times through out the week dnsmasq-dhcp would stop issuing IP addresses and I can only connect on the LAN with static IP (as I am this second). I initially had the router reboot every night and I never saw the issue but with my work I need to keep the VPN active through the night.

Any thoughts on what might causing this and if it is perhaps a HW issue ?

These are the only logs I see pertaining to this (192.168.1.100 is one device that is showing (Network_selection_diabled_DHCP_Failure)

Mar 3 07:55:27 dnsmasq-dhcp[565]: DHCPDISCOVER(br0) b8:d7:af:01:10:b3
Mar 3 07:55:27 dnsmasq-dhcp[565]: DHCPOFFER(br0) 192.168.1.100 b8:d7:af:01:10:b3
Mar 3 07:55:27 dnsmasq-dhcp[565]: DHCPDISCOVER(br0) b8:d7:af:01:10:b3
Mar 3 07:55:27 dnsmasq-dhcp[565]: DHCPOFFER(br0) 192.168.1.100 b8:d7:af:01:10:b3
Mar 3 07:55:28 kernel: net_ratelimit: 13 callbacks suppressed
Mar 3 07:55:29 dnsmasq-dhcp[565]: DHCPDISCOVER(br0) b8:d7:af:01:10:b3
Mar 3 07:55:29 dnsmasq-dhcp[565]: DHCPOFFER(br0) 192.168.1.100 b8:d7:af:01:10:b3
Mar 3 07:55:29 dnsmasq-dhcp[565]: DHCPDISCOVER(br0) b8:d7:af:01:10:b3
Mar 3 07:55:29 dnsmasq-dhcp[565]: DHCPOFFER(br0) 192.168.1.100 b8:d7:af:01:10:b3
Mar 3 07:55:33 dnsmasq-dhcp[565]: DHCPDISCOVER(br0) b8:d7:af:01:10:b3
Mar 3 07:55:33 dnsmasq-dhcp[565]: DHCPOFFER(br0) 192.168.1.100 b8:d7:af:01:10:b3
Mar 3 07:55:33 dnsmasq-dhcp[565]: DHCPDISCOVER(br0) b8:d7:af:01:10:b3
Mar 3 07:55:33 dnsmasq-dhcp[565]: DHCPOFFER(br0) 192.168.1.100 b8:d7:af:01:10:b3
Mar 3 07:55:42 dnsmasq-dhcp[565]: DHCPDISCOVER(br0) b8:d7:af:01:10:b3
Mar 3 07:55:42 dnsmasq-dhcp[565]: DHCPOFFER(br0) 192.168.1.100 b8:d7:af:01:10:b3
Mar 3 07:55:42 dnsmasq-dhcp[565]: DHCPDISCOVER(br0) b8:d7:af:01:10:b3
Mar 3 07:55:42 dnsmasq-dhcp[565]: DHCPOFFER(br0) 192.168.1.100 b8:d7:af:01:10:b3

Uptime 0 days 17 hours 33 minute(s) 47 seconds
Temperatures 2.4 GHz: 50°C - 5 GHz: 54°C - CPU: 77°C
CPU
CPU Model ARMv7 Processor rev 0 (v7l) - (Cores: 2)
CPU Frequency 1400 MHz
CPU Load Average (1, 5, 15 mins) 1.05, 1.07, 1.11
Memory
Total 503.23 MB
Free 356.94 MB
Buffers 0.95 MB
Cache 14.04 MB
Swap 0.00 / 0.00 MB
Internal Storage
NVRAM usage 68001 / 131072 bytes
JFFS 2.74 / 64.00 MB
Network
HW acceleration Enabled
Connections 250 / 300000 - 46 active

Ethernet Ports
Port VLAN Link State Last Device Seen
WAN 2 1000 Full Duplex CE:E1:7F:1A:B2:12
LAN 1 1 1000 Full Duplex D4:817:0B:C6:11
LAN 2 1 1000 Full Duplex D4:817:0B:C6:11
LAN 3 1 Down
LAN 4 1 Down

Wireless clients (2.4 GHz) Associated: 2 - Authorized: 2 - Authenticated: 2
Wireless clients (5 GHz) Associated: 3 - Authorized: 3 - Authenticated: 3


Than you

 

[john9527]

I'd be looking at the client, not the router. The client is making the DISCOVER request, the router responds with an OFFER which is apparently ignored by the client, which issues another DISCOVER.

Is this an Apple device? This is a know problem for example with AppleTV wireless.

 

[PIO1]

I'd be looking at the client, not the router. The client is making the DISCOVER request, the router responds with an OFFER which is apparently ignored by the client, which issues another DISCOVER.

Is this an Apple device? This is a know problem for example with AppleTV wireless.

Hi -

I am seeing this on a few devices that don't have static IP. The one above is an android but I have an apple (TV and iphone) as well seeing the same. None of the device with dhcp lease seems to be up and they they fail to get an IP.

 

[PIO1]

Ok so I think I found the root. Once I broke the two port link aggregation lan bond going to the netgear switch the devices acquired a dhcp lease. I am guessing the router was getting flooded with packets. One step closer

 

[PIO1]

I went port by port even tried another switch, same issue. Only when I stopped/started the link aggregation on the router did the flooding stop and dhcp requests were handled correctly. Is this is an issue with the firmware, perhaps the way it handles the bond (I saw no logs)? That explains why when the router was rebooted at night I never saw the issue. Thanks!