Received DHCP NAK -- Can't connect with ISP

dougK44883 · January 3, 2022, 6:22pm

Netgear R7800. Used stock firmware to confirm it works, yes. Installed OpenWrt, figured out how to change WAN MAC so ISP will give it an IP all I get is

Sun Jan  2 21:46:12 2022 daemon.notice netifd: wan (1374): udhcpc: sending select for 000.000.10.91
Sun Jan  2 21:46:12 2022 daemon.notice netifd: wan (1374): udhcpc: received DHCP NAK

Presuming I had not gotten the MAC setting correct I followed: https://openwrt.org/docs/guide-quick-start/checks_and_troubleshooting and connected it via another router (R7000 running FreshTomato). According to it's device list it's MAC is correct.

Compared logs from R7000 udhcpc shows:

Dec 31 19:00:20 r7000 daemon.info udhcpc[1112]: broadcasting discover
Dec 31 19:00:21 r7000 daemon.info udhcpc[1112]: broadcasting select for 000.000.172.40, server 000.000.31.129

and later

daemon.info udhcpc[1504]: sending renew to server 000.000.31.129

OpenWrt is asking on xxx.xxx.10.91 while "everything else" is using xxx.xxx.31.129 -- what do you suppose is up with that? (in the interim I had installed dd-wrt, also worked as expected)

I have fixed wireless. I've had the radio device changed out a few times, my IP stays constant until the hardware changes or I ask them to change my MAC.
From what I've gathered, one may be my gateway - the radio device. While the other is the connection - end point, between the radio and the tower.
But I'm not a technician, some logs from different systems, through versions had varying log information.

Is there anything I can do? What diagnosis may help dig into this? What basic function have overlooked?

trendy · January 3, 2022, 9:49pm

You could post the network configuration for a start and we can plan accordingly afterwards.
uci export network; ip -s link

dougK44883 · January 3, 2022, 10:35pm

root@r7800:~# uci export network; ip -s link
package network

config interface 'loopback'
	option device 'lo'
	option proto 'static'
	option ipaddr '127.0.0.1'
	option netmask '255.0.0.0'

config globals 'globals'
	option ula_prefix 'fd1c:85a4:cb81::/48'

config device
	option name 'br-lan'
	option type 'bridge'
	list ports 'eth1.1'

config interface 'lan'
	option device 'br-lan'
	option proto 'static'
	option netmask '255.255.255.0'
	option ip6assign '60'
	option ipaddr '172.16.0.1'

config interface 'wan'
	option device 'eth0.2'
	option proto 'dhcp'

config interface 'wan6'
	option device 'eth0.2'
	option proto 'dhcpv6'

config switch
	option name 'switch0'
	option reset '1'
	option enable_vlan '1'

config switch_vlan
	option device 'switch0'
	option vlan '1'
	option ports '1 2 3 4 6t'

config switch_vlan
	option device 'switch0'
	option vlan '2'
	option ports '5 0t'

config device
	option name 'eth0'
	option macaddr 'XX:XX:X:5B:A7:DB'

BusyBox v1.33.1 (2021-10-24 09:01:35 UTC) multi-call binary.

Usage: ip [OPTIONS] address|route|link|neigh|rule [ARGS]

OPTIONS := -f[amily] inet|inet6|link | -o[neline]

ip addr add|del IFADDR dev IFACE | show|flush [dev IFACE] [to PREFIX]
ip route list|flush|add|del|change|append|replace|test ROUTE
ip link set IFACE [up|down] [arp on|off] [multicast on|off]
	[promisc on|off] [mtu NUM] [name NAME] [qlen NUM] [address MAC]
	[master IFACE | nomaster]
ip neigh show|flush [to PREFIX] [dev DEV] [nud STATE]
ip rule [list] | add|del SELECTOR ACTION

root@r7800:~# ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
    link/ether xx:xx:xx:5b:a7:db brd ff:ff:ff:ff:ff:ff
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
    link/ether xx:xx:xx:1f:ef:f9 brd ff:ff:ff:ff:ff:ff
5: wlan0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 1000
    link/ether xx:xx:xx:1f:ef:fb brd ff:ff:ff:ff:ff:ff
6: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 1000
    link/ether xx:xx:xx:1f:ef:fc brd ff:ff:ff:ff:ff:ff
7: br-lan: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
    link/ether xx:xx:xx:1f:ef:f9 brd ff:ff:ff:ff:ff:ff
8: eth1.1@eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-lan state UP qlen 1000
    link/ether xx:xx:xx:1f:ef:f9 brd ff:ff:ff:ff:ff:ff
9: eth0.2@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
    link/ether xx:xx:xx:5b:a7:db brd ff:ff:ff:ff:ff:ff

trendy · January 4, 2022, 10:37am

uci set network.wan.broadcast='1'; uci commit network; ifup wan

dougK44883 · January 5, 2022, 12:27am

to back up a bit, while I was running the prior commands, here's an excerpt from system log

Sun Jan  2 21:39:27 2022 daemon.notice netifd: wan (1369): udhcpc: sending select for 000.000.10.91
Sun Jan  2 21:39:27 2022 daemon.notice netifd: wan (1369): udhcpc: received DHCP NAK
Sun Jan  2 21:39:30 2022 daemon.notice netifd: wan (1369): udhcpc: sending select for 000.000.10.91
Sun Jan  2 21:39:30 2022 daemon.notice netifd: wan (1369): udhcpc: received DHCP NAK
Sun Jan  2 21:39:34 2022 daemon.notice netifd: wan (1369): udhcpc: sending select for 000.000.10.91
Sun Jan  2 21:39:34 2022 daemon.notice netifd: wan (1369): udhcpc: received DHCP NAK
Sun Jan  2 21:39:37 2022 daemon.notice netifd: wan (1369): udhcpc: sending select for 000.000.10.91
Sun Jan  2 21:39:37 2022 daemon.notice netifd: wan (1369): udhcpc: received DHCP NAK
Sun Jan  2 21:39:40 2022 daemon.notice netifd: wan (1369): udhcpc: sending select for 000.000.10.91
Sun Jan  2 21:39:41 2022 daemon.notice netifd: wan (1369): udhcpc: received DHCP NAK
Sun Jan  2 21:39:44 2022 daemon.notice netifd: wan (1369): udhcpc: sending select for 000.000.10.91
Sun Jan  2 21:39:44 2022 daemon.notice netifd: wan (1369): udhcpc: received DHCP NAK
Sun Jan  2 21:39:47 2022 daemon.notice netifd: wan (1369): udhcpc: sending select for 000.000.10.91
Sun Jan  2 21:39:47 2022 daemon.notice netifd: wan (1369): udhcpc: received DHCP NAK

uci set network.wan.broadcast='1'; uci commit network; ifup wan
no output on the command line, from syslog -

Mon Jan  3 17:38:13 2022 daemon.notice netifd: wan (2197): Command failed: Permission denied
Mon Jan  3 17:38:13 2022 daemon.notice netifd: Interface 'wan' is now down
Mon Jan  3 17:38:13 2022 daemon.notice netifd: Interface 'wan' is setting up now
Mon Jan  3 17:38:13 2022 daemon.notice netifd: wan (2560): udhcpc: started, v1.33.1
Mon Jan  3 17:38:13 2022 daemon.notice netifd: wan (2560): udhcpc: sending discover
Mon Jan  3 17:38:13 2022 daemon.notice netifd: wan (2560): udhcpc: sending select for 000.000.10.91
Mon Jan  3 17:38:13 2022 daemon.notice netifd: wan (2560): udhcpc: received DHCP NAK

and began repeating again. To be clear, I masked the IP with 000.000

Although it appears to receive a response from the IP, when I try to ping the same IP (when connected) from the R7000 (w/FreshTomato) it's unreachable.
again, when I took the ISP/WAN cable from R7800 (OpenWrt) and connected to R7000 it's log shows it's getting it's IP from a different server
Jan 4 16:04:36 r7000 daemon.info udhcpc[3434]: lease of 000.000.172.40 obtained from 000.000.31.129, lease time 28800
The 0s are the same. This same router worked with stock firmware I don't have another compatible OpenWrt router for elimination processes.
I did give dd-wrt a run with success, but I think I really want to graduate to OpenWrt. Or I thought I did.
I have a bit of a clue when things are working right, but I have no real idea where this is coming from and know it's a waste of time to try to ask technical stuff with customer support.

trendy · January 5, 2022, 10:59am

Which OpenWrt version are you running?

ubus call system board

Can you confirm that the broadcast option was accepted? uci show network.wan
The last thing we can check is to capture the packets and verify that the mac and other options are sent correctly.

opkg update; opkg install tcpdump; tcpdump -i eth0.2 -evn udp port 67 & \
sleep 2; \
killall -SIGUSR1 udhcpc; \
sleep 20; \
killall tcpdump

dougK44883 · February 5, 2022, 2:22pm

Spent days snowed in, so... I reset to defaults (as performed in the past, more than once), changed the WAN MAC and maybe tweaked here and there until eventually it worked.

It's great to use a grownup's firmware.

trendy · February 5, 2022, 8:17pm

If your problem is solved, please consider marking this topic as [Solved]. See How to mark a topic as [Solved] for a short how-to.

system · February 15, 2022, 8:17pm

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