dnsmasq error

[iAirJordan]

Jan 18 01:37:20 dnsmasq-dhcp[380]: DHCPNAK(br0) 192.168.2.20 24:a2:e1:d7:81:d4 wrong address
Jan 16 23:59:48 dnsmasq-dhcp[380]: DHCPNAK(br0) 192.168.1.112 24:a2:e1:d7:81:d4 wrong address

i get these in my error log. somehow its assigning the wrong ip to this device? idk what causes it either.

 

[sinshiva]

prbably another router with dhcp/dnsmasq enabled

 

[saintdev]

Is this a wireless device?

A lot of wireless devices will attempt to use a shortcut to cut down on the time needed to reacquire a lease.

Instead of the typical DHCP process:

#Client connects to network
client: DHCPDISCOVER
server: DHCPOFFER x.x.x.x
client: DHCPREQUEST x.x.x.x
server: DHCPACK x.x.x.x

The wireless client will use the last known IP address and immediately request it again.

#Client connects to network
client: DHCPREQUEST x.x.x.x
server: DHCPACK x.x.x.x

If the client is switching networks, say from a public wifi to your private network, and they use different IP address ranges. You will see exactly this behavior when the client connects because it is attempting to connect more quickly with the last IP address it used.

#Client connects to network
client: DHCPREQUEST y.y.y.y
server: DHCPNACK y.y.y.y
client: DHCPDISCOVER
server: DHCPOFFER x.x.x.x
client: DHCPREQUEST x.x.x.x
server: DHCPACK x.x.x.x

Or as sinshiva says, there is another DHCP server running on your network.

 

[iAirJordan]

Yea it is an iphone. And i only have one router. thankyou for the helpful info^^

 

[jlake]

If you only have one router at home, you have nothing to worry about. I get that message all the time when I switch Apple TV back and forth between two different routers (two different LAN segments). Apple TV causes the same message because it tries to connect to other router first. So even if you have two routers, it won't be a problem if you have them cascaded/configured properly in a LAN to WAN cascade.

 

[sinshiva]

Is this a wireless device?

A lot of wireless devices will attempt to use a shortcut to cut down on the time needed to reacquire a lease.

Instead of the typical DHCP process:

#Client connects to network
client: DHCPDISCOVER
server: DHCPOFFER x.x.x.x
client: DHCPREQUEST x.x.x.x
server: DHCPACK x.x.x.x

The wireless client will use the last known IP address and immediately request it again.

#Client connects to network
client: DHCPREQUEST x.x.x.x
server: DHCPACK x.x.x.x

If the client is switching networks, say from a public wifi to your private network, and they use different IP address ranges. You will see exactly this behavior when the client connects because it is attempting to connect more quickly with the last IP address it used.

#Client connects to network
client: DHCPREQUEST y.y.y.y
server: DHCPNACK y.y.y.y
client: DHCPDISCOVER
server: DHCPOFFER x.x.x.x
client: DHCPREQUEST x.x.x.x
server: DHCPACK x.x.x.x

Or as sinshiva says, there is another DHCP server running on your network.

cool, never knew that