OpenWrt Forum Archive

Topic: dynamic IP

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Post #1
Sajty
12 Aug 2009, 14:39

Hi

I have Cable connection with dynamic IP but when my IP changes OpenWRT doesn't refreshes IP. (lan works but wan not)
It's the same thing when I restart Cable modem.
I need manually reload network everytime.
Is it ISP or OpenWRT related problem?

I have Asus wl-500gp v1.
Tried 2.6 and 2.4 too.

/etc/config/network

config 'switch' 'eth0'
    option 'vlan0' '1 2 3 4 5*'
    option 'vlan1' '0 5'

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

config 'interface' 'lan'
    option 'type' 'bridge'
    option 'ifname' 'eth0.0'
    option 'proto' 'static'
    option 'ipaddr' '192.168.1.1'
    option 'netmask' '255.255.255.0'

config 'interface' 'wan'
    option 'ifname' 'eth0.1'
    option 'proto' 'dhcp'
    option 'defaultroute' '0'
    option 'peerdns' '0'

/etc/config/dhcp

config 'dnsmasq'
    option 'local' '/lan/'
    option 'domain' 'lan'
    option 'leasefile' '/tmp/dhcp.leases'
    option 'resolvfile' '/tmp/resolv.conf.auto'
    option 'domainneeded' '1'
    option 'authoritative' '1'
    option 'boguspriv' '1'
    option 'localise_queries' '1'
    option 'expandhosts' '1'
    option 'readethers' '1'

config 'dhcp' 'lan'
    option 'interface' 'lan'
    option 'start' '100'
    option 'limit' '150'
    option 'leasetime' '12h'
    option 'ignore' '0'

config 'dhcp' 'wan'
    option 'interface' 'wan'
    option 'ignore' '1'
Post #2
dr.gonzo42
12 Aug 2009, 15:10

Is there a dhcp-server running on the cable modem?
I think the dynamic IP changes at the outgoing network device on the modem and not at the internal, there should be a static none. You can give the wan device of the asus a static IP with gateway and dns adresses of the internal network of the router and it should work.

Post #3
MMCM
12 Aug 2009, 23:48

Is the lease time correct for the IP on the WAN interface?
See the system log for messages from udhcpc.
If the lease time reported does not match (i. e. is too long), udhcpc will not request a new IP in time.

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