Unexpected DHCP behavior

[Elmo]

I just updated my router setup. I used to have my WRT-router (WRT) connected to the router (Rout) built into my ISP's modem hardware. I now turned Rout off so that WRT is facing Internet. For that I inserted netmask and gateway of my ISP and the DNS servers of my ISP .

1. I did not change the internal (lan interface) IP address of the router and it is still static. I also did not change the DHCP setup at all. But after the update the DHCP server is now giving me addresses like 192.168.0.x indstead of 192.168.1.x. What happened ?

2. When i try to change the lan interface IP address to something else than 192.168.1.1 the Luci interface will not save. It simply times out. Is there any reason why this is a problem ?

Thanks

[lleachii]

@Elmo

What happened ?

You'd have to tell us. As you've correctly noted, 192.168.1.0/24 is the default LAN subnet on official OpenWrt firmware.

@Elmo

It simply times out. Is there any reason why this is a problem ?

• Did you see a big red button after the timeout that says "Apply Unchecked"?
• The reason would be the safety revert on the web GUI. Making the changes via CLI or configs for example won't cause this issue.

@Elmo

When i try to change the lan interface IP address to something else than 192.168.1.1

I assume xxx.xxx.1.1 was a typo - and you meant 0.1?

EDIT: Using Windows, or wireshark, tcpdump, etc., you can verify the MAC of the DHCP server issuing the IP addresses. I assume you verified the ISP's device as not issuing DHCP leases, correct?

[Elmo]

@lleachii

You'd have to tell us. As you've correctly noted, 192.168.1.0/24 is the default LAN subnet on official OpenWrt firmware.

Not quite sure if i understand. The IP address of the lan interface was never changed and it was set to 192.168.1.1 and the DHCP server gave IP's starting with 192.168.1.x and gives IP addresses like 192.168.0.x. Sorry for the inconvenience

[lleachii]

@Elmo

The IP address of the lan interface was never changed and it was set to 192.168.1.1 and the DHCP server gave IP's starting with 192.168.1.x

Correct.

@Elmo

and gives IP addresses like 192.168.0.x.

So you're saying that your router just started giving out wrong IPs in the 192.168.0.0/24 range - yet it was still numbered 192.168.1.1/24?

If so, please explain how you connected to the OpenWrt at 192.168.1.1?

Also:

@lleachii

I assume you verified the ISP's device as not issuing DHCP leases, correct?

[Elmo]

@lleachii

• Did you see a big red button after the timeout that says "Apply Unchecked"?
• The reason would be the safety revert on the web GUI. Making the changes via CLI or configs for example won't cause this issue.

Yes I did see that. Would it course any problems just changing it directly in /etc/config/network I think it is ?

[Elmo]

@lleachii

So you're saying that your router just started giving out wrong IPs in the 192.168.0.0/24 range - yet it was still numbered 192.168.1.1/24?

Exactly ... it started giving out "wrong" IPs. And it is both wireless and wired clients !!!

[lleachii]

@Elmo

Would it course any problems just changing it directly in /etc/config/network I think it is ?

I think you asked if it would cause any problems editing in /etc/config/network ?

Maybe - if you didn't restart everything. Did you do an:

/etc/init.d/network restart
/etc/init.d/dnsmasq restart

after saving???

[Elmo]

@lleachii

/etc/init.d/network restart
/etc/init.d/dnsmasq restart

No did not ... I will do that right away ... sorry for bad spelling ... I am not native English speaking

[Elmo]

@lleachii

/etc/init.d/network restart
/etc/init.d/dnsmasq restart

Did not help .. still giving addresses in 192.168.1.0/24 range

[lleachii]

Then:

reboot

???

---

If that doesn't work:

Please copy the output of the following commands and post it here using the "Preformatted text </> " button:

Remember to redact passwords, MAC addresses and any public IP addresses you may have:

cat /etc/config/network
cat /etc/config/wireless
cat /etc/config/dhcp
cat /etc/config/firewall

@Elmo

.. still giving addresses in 192.168.1.0/24 range

???

@Elmo

and gives IP addresses like 192.168.0.x.

???

Yea, post configs, I'm not sure if you're making typos, confused or...

[Elmo]

@Elmo

Would it course any problems just changing it directly in /etc/config/network I think it is ?

I just tried to alter the lan IP address in the /etc/config/network file and did an /etc/init.d/network restart ... now the system is hanging

[lleachii]

@Elmo

... now the system is hanging

No, you lost connection because you changed the IP and:

• need to obtain an IP in the new range on the client
• browse to/use the new OpenWrt/LuCI IP you configured

[Elmo]

@lleachii

No, you lost connection because you changed the IP and:

Yeah ... thank you for being what should have been my brain

[Elmo]

@lleachii

No, you lost connection because you changed the IP and:

But Luci will not connect to the new IP adresse

[lleachii]

@Elmo

Luci will not connect to the new IP adresse

Please paste the configs as noted.

• Did you get a new DHCP lease in the new IP range???
• What did you make the new IP (just curious)?
• Are you making changes over WiFi?

(You've got to provide details, you're literally changing the router's IP and not being clear on what you're doing to re-establish connectivity.)

[Elmo]

@lleachii

Please paste the configs as noted.

/etc/config/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 'fda1:0812:9c34::/48'

config device
	option name 'br-lan'
	option type 'bridge'
	list ports 'lan1'
	list ports 'lan2'
	list ports 'lan3'
	list ports 'lan4'

config interface 'lan'
	option device 'br-lan'
	option proto 'static'
	option ipaddr '10.12.17.81'
	option delegate '0'
	option ipv6 'off'
	option netmask ''
	option gateway '
	list dns ''
	list dns ''

config device
	option name 'wan'
	option macaddr 'c2:56:27:73:36:cf'
	option ipv6 '0'

config interface 'wan'
	option device 'wan'
	option proto 'dhcp'
	option type 'bridge'
	option delegate '0'
	option ipv6 'off'

config interface 'Guest'
	option proto 'static'
	option ipaddr '192.168.9.1'
	option netmask '255.255.255.0'
	list dns '8.8.8.8'
	list dns '1.1.1.1'

config interface 'tvwifi'
	option proto 'static'
	option ipaddr '192.168.15.1'
	option netmask '255.255.255.0'
	list dns '8.8.8.8'
	list dns '1.1.1.1'

[Elmo]

@lleachii

Did you get a new DHCP lease in the new IP range???

Cannot connect to Luci ... how do I see connections on the box (terminal)

[Elmo]

@lleachii

Please paste the configs as noted.

/etc/config/wireless:

config wifi-device 'radio0'
	option type 'mac80211'
	option path 'soc/soc:pcie/pci0000:00/0000:00:01.0/0000:01:00.0'
	option band '5g'
	option htmode 'VHT80'
	option country 'FR'
	option cell_density '1'
	option channel 'auto'

config wifi-device 'radio1'
	option type 'mac80211'
	option path 'soc/soc:pcie/pci0000:00/0000:00:02.0/0000:02:00.0'
	option band '2g'
	option country 'FR'
	option cell_density '0'
	option htmode 'HT40'
	option channel '13'

config wifi-iface 'wifinet0'
	option device 'radio0'
	option mode 'ap'
	option ssid 'vindue24rose12bil'
	option network 'lan'
	option encryption 'sae'
	option key '-)07928173KLUT.>&83726kiRbMaqp95#mnBr57382*-<z'

config wifi-iface 'wifinet1'
	option device 'radio1'
	option mode 'ap'
	option network 'lan'
	option ssid 'cykel16pasta54stang'
	option encryption 'sae'
	option key '883929E(.20304772516284508467288'

config wifi-iface 'wifinet2'
	option device 'radio1'
	option mode 'ap'
	option isolate '1'
	option ssid 'WLJP'
	option network 'Guest'
	option key 'kJu746282939).&'
	option encryption 'sae'
	option wpa_disable_eapol_key_retries '1'

config wifi-iface 'wifinet3'
	option device 'radio1'
	option mode 'ap'
	option ssid 'PWIFI'
	option encryption 'psk2'
	option isolate '1'
	option network 'tvwifi'
	option key '.4727Hjeiils638.01294'

config wifi-iface 'wifinet4'
	option device 'radio0'
	option mode 'ap'
	option ssid 'Walter'
	option key 'znBu99dkD989NDk'
	option wpa_disable_eapol_key_retries '1'
	option network 'lan'
	option encryption 'psk2'
	option ieee80211w '2'

config wifi-iface 'wifinet5'
	option device 'radio0'
	option mode 'ap'
	option ssid 'Fakta'
	option encryption 'psk2'
	option network 'lan'
	option key 'jfkfiei(>ieiKjd7932-,/5#f3211'
	option ieee80211w '2'
	option wpa_disable_eapol_key_retries '1'

[Elmo]

/etc/config/dhcp:

config dnsmasq
	option domainneeded '1'
	option boguspriv '1'
	option filterwin2k '0'
	option localise_queries '1'
	option rebind_protection '1'
	option rebind_localhost '1'
	option local '/lan/'
	option domain 'lan'
	option expandhosts '1'
	option nonegcache '0'
	option authoritative '1'
	option readethers '1'
	option leasefile '/tmp/dhcp.leases'
	option resolvfile '/tmp/resolv.conf.d/resolv.conf.auto'
	option nonwildcard '1'
	option localservice '1'
	option ednspacket_max '1232'

config dhcp 'lan'
	option interface 'lan'
	option limit '150'
	option dhcpv4 'server'
	option ra 'server'
	list ra_flags 'managed-config'
	list ra_flags 'other-config'
	option leasetime '5h'
	option start '10'

config dhcp 'wan'
	option interface 'wan'
	option ignore '1'
	list ra_flags 'none'

config odhcpd 'odhcpd'
	option maindhcp '0'
	option leasefile '/tmp/hosts/odhcpd'
	option leasetrigger '/usr/sbin/odhcpd-update'
	option loglevel '4'

config dhcp 'Guest'
	option interface 'Guest'
	option limit '150'
	option leasetime '12h'
	option start '150'
	list ra_flags 'none'

config dhcp 'tvwifi'
	option interface 'tvwifi'
	option start '150'
	option limit '1'
	option leasetime '2'
	list ra_flags 'none'

[lleachii]

???

Please paste all configs requested if you desire assistance, please. You can use one post. DHCP?

@Elmo

on the box (terminal)

???
Serial or...?

• How are you connecting to the OpenWrt?
• Are you using WAN - why is the config changed?

@Elmo

list dns '8.8.8.8'

Remove.

@Elmo

wireless

You failed to redact your keys.

@Elmo

	option limit '1'
	option leasetime '2'

???