[PLUG] WRT54G DHCP - always serve the same IP address to a particular device?

[Richard C. Steffens]

On 01/22/2012 03:34 PM, Jason LaPier wrote:
> On Sun, Jan 22, 2012 at 3:18 PM, Richard C. Steffens<rsteff at comcast.net>wrote:
>> Is it possible to tell my WRT54G to always serve the same IP address to
>> a particular device?
> You want to go into the DHCP server configuration section and add static
> IPs by MAC address. I'm using the DD-WRT firmware for my WRT54G, and it's
> under the Services tab (first page, also called Services). At the bottom of
> the DHCP section, there is a place to add static addresses.
On 01/22/2012 03:58 PM, Aaron Burt wrote:
>> Sure.  I think the stock firmware allows you to set "reserved" or "static"
>> DHCP assignments.  I know that the Tomato replacement firmware does.
On 01/22/2012 05:15 PM, wes wrote:
> It is offered on my Linksys WRT300N. I seem to recall the lower base models
> don't have this option. On my Basic Setup screen, there is an entry for
> "DHCP Server: Enabled or Disabled" and to the right of that is a button
> labeled "DHCP Reservation." I would not be surprised to find this is
> missing from your model.

Alas, Wes is correct. I don't find "DHCP Reservation" in my WRT54G 
administration browser interface.

Here are the first four options in the Network Address Server Settings 
section on the Basic Setup tab:

DHCP Server:             (*) Enable ( ) Disable
Starting IP Address:     192.168.0.[100]
Maximum Number
of DHCP Users:           [50]
Client Lease Time:       [0] minutes (0 means one day)

There appears to be nothing related to reserving an IP address within 
the DHCP range.

>> The other is to change the lease time to longer than a week. I'm not
>> sure how this helps, but that was what was recommended. I think it has
>> to do with the RTV rebooting itself more than once a week. But why the
>> lease duration would make any difference to the RTV when it's DHCP bug
>> kicks in isn't clear to me.
> In my WRT300N interface, the highest I can push my lease time is 9999
> minutes, or just shy of 1 week. At least it's better than the default of 1
> day. I guess the theory behind this being potentially helpful is that if
> the router gets a DHCP request from a client that already has an active
> lease, it will automagically reassign the same IP back to it. This should
> also be happening when it's within the 1 day window, so I am pretty
> skeptical that this could help.

If I keep an eye on the ReplayTV by pinging it every so often I should 
see it go get an IP address via DHCP. I can then figure out what address 
it got and change the WiRNS configuration to look for the RTV at that 
address. I would also reconfigure the RTV to use that address as it's 
static address. And if I set the Client Least Time to 9999 I'll get 6.9 
something days at that IP address. If most of the devices in the house 
with IP addresses are set to static, maybe the same address will be 
assigned to the RTV serendipitously?

-- 
Regards,

Dick Steffens