IP address incorrectly assigned on boot

[Rick Stevens]

On 02/03/2012 02:39 PM, Geoffrey Leach wrote:
> On 02/03/2012 01:54:34 PM, j.e.aneiros wrote:
>> On Fri, Feb 3, 2012 at 4:01 PM, Geoffrey Leach<geoff at hughes.net>
>> wrote:
>>
>>> A system on my local network (pvr) has its IP address in /etc/hosts
>>>
>>> geoff at pvr[1]->cat /etc/hosts
>>> 127.0.0.1   localhost localhost.localdomain localhost4
>>> localhost4.localdomain4
>>>
>>> 192.168.10.2    pvr.mtranch.com pvr
>>> 192.168.10.3    mtranch.mtranch.com mtranch
>>> 192.168.10.1    Netgear
>>> 198.168.20.5    Homerun
>>>
>>> Netgear router accessed from pvr via wireless. It has the address
>>> 192.168.10.2 reserved and assigned to pvr. Worked fine.  Today
>> after
>>> booting up the latest kernel, (3.2.2-1.fc16.i686.PAE), the IP
>> address
>>> has changed to 192.168.10.5:
>>>
>>> geoff at pvr[2]->ifconfig wlan0
>>> wlan0     Link encap:Ethernet  HWaddr AE:5D:BA:91:67:2D
>>>           inet addr:192.168.10.5  Bcast:192.168.10.255
>>> Mask:255.255.255.0
>>>           inet6 addr: fe80::ac5d:baff:fe91:672d/64 Scope:Link
>>>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>>>           RX packets:484 errors:0 dropped:0 overruns:0 frame:0
>>>           TX packets:462 errors:0 dropped:0 overruns:0 carrier:0
>>>           collisions:0 txqueuelen:1000
>>>
>>> you'll note that it is 192.168.10.5
>>>
>>> Not surprisingly, I can't ssh 192.168.10.2, but I can ssh
>> 192.168.10.5
>>>
>>> Question: where is this (dynamic?) assignment taking place?
>>>
>>
>> I think the machine is requesting the router a new IP and the router
>> couldn't match the MAC of the request with the MAC associated to the
>> reserved IP 192.168.10.2, so is giving a new IP in the range.
>> Something
>> change at the machine, did you check the MAC AE:5D:BA:91:67:2D
>> against
>> your
>> rule in the router?
>
> Your suspicion was correct. I replaced the one in use with the one from
> ifconfig. Unfortunately that did not fix the problem.
>
> I need a tutorial on assigning MAC addresses, as they are inconsistent
> on the server and client. Is it correct that the MAC address is the
> same as HWADDR in the ifcfg file? And why would the value change when
> the hardware did not?

They're supposed to be the same.  The only way to be sure is to actually
see what the driver assigned as the MAC address:

	$ cat /sys/class/net/wlan0/address

What's returned by that is the MAC address as set up by the driver.
That should match the value in the ifcfg file's HWADDR field.
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- Rick Stevens, Systems Engineer, AllDigital    ricks at alldigital.com -
- AIM/Skype: therps2        ICQ: 22643734            Yahoo: origrps2 -
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-     If you can't beat your computer at chess...try kickboxing!     -
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