Dhcp not working on WAN to ISP router, static IP working but no internet

Installing and Using OpenWrt
#1

Hi,

I have installed OpenWrt 17.01.6 on my old D-LINK DIR-600 rev.B2. Lan & Wifi are working correctly however when I try to connect the WAN port to my ISP router (a Huawei HG8045H) as a DHCP client it does not seem to be able to get an IP.
Here is my setup:
archi_maison

When I use it as a dhcp client, udhcpc seems to send requests and that's it : daemon.notice netifd: wan (1888): udhcpc: sending discover
When I use static IP, I can ping 192.168.100.1 but not 8.8.8.8 for example.

Any idea in what could be wrong ? I've even tried to put the IP in DMZ on my ISP router without success.

Thank you in advance.

#2

Perhaps MAC address filtering on the ISP router.

See also:

1 Like
#3
  • Can you check the cable? If you connect some other device with the same cable to the same port (#4) does it work? Did you try other ports?
  • Check also MTU on the wan interface that it is 1500.
  • Did you change anything in the firewall rules by any chance? The default ones should work out of the box.
  • I'd ask you to run tcpdump, but I am not sure if you can get internet on the DIR-600 somehow.
3 Likes
#4

No MAC filtering or anything.

#5
  • What about network.wan.clientid?
  • Also note the reply from @trendy.
#6

Thank you for your answer:

  • I have tried different cables and ports.
  • MTU is not overridden, set at 1500 by default
  • I use the default firewall rules
  • tcpdump does not seem installed by default isn't it ? Should I install it ?

I have no clientid configured.

Here is my config /etc/config/network:

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

config globals 'globals'
        option ula_prefix 'fd19:8f6c:9bf2::/48'

config interface 'lan'
        option type 'bridge'
        option ifname 'eth0.1'
        option proto 'static'
        option ipaddr '192.168.1.1'
        option netmask '255.255.255.0'
        option ip6assign '60'

config device 'lan_dev'
        option name 'eth0.1'
        option macaddr 'fc:75:16:99:e3:5c'

config interface 'wan'
        option _orig_ifname 'eth0.2'
        option _orig_bridge 'false'
        option ifname 'eth0.2'
        option proto 'static'
        option ipaddr '192.168.100.1'
        option netmask '255.255.255.0'
        option gateway '192.168.100.1'
        option dns '8.8.8.8'

config device 'wan_dev'
        option name 'eth0.2'
        option macaddr 'fc:75:16:99:e3:5d'

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

config switch
        option name 'rt305x'
        option reset '1'
        option enable_vlan '1'

config switch_vlan
        option device 'rt305x'
        option vlan '1'
        option ports '0 1 2 3 6t'

config switch_vlan
        option device 'rt305x'
        option vlan '2'
        option ports '4 6t'
1 Like
#7

You cannot have same IP for address and gateway.

If you can manage to connect the router somehow on the internet, it would help troubleshoot the DHCP packet exchange.

2 Likes
#8

You are correct my bad, I already changed the IP to 192.168.100.10 but forgot to export the config again after. I managed to connect to the other router at 192.168.100.1 but not the internet :s I am gonna have a look at tcpdump then.

#9

Alright, let's see them all together in action:

cat /etc/config/network; cat /etc/config/firewall ; cat /etc/config/dhcp ; ip -4 addr ; ip -4 ro ; ip -4 ru; traceroute 8.8.8.8; nslookup www.google.com;
1 Like
#10

Yes correct, for the IP in fact it is 192.168.100.10 for my openwrt router and 192.168.100.1 being the isp router, I've fixed it earlier forgot to export the config again. I am gonna have a look to tcpdump then.