hmmm, looks like I was incorrect according to this...

>From "Lease Renewals"
http://technet.microsoft.com/en-us/library/cc958919.aspx

If the client is unable to communicate with its original DHCP server, the
client waits until 87.5 percent of its lease time elapses. Then the client
enters a rebinding state, broadcasting (with a maximum of three retries at
4, 8, and 16 seconds) a DHCPDiscover message to any available DHCP server to
update its current IP address lease.

Jeff


On Fri, May 1, 2009 at 2:17 PM, Jeff Bunting <[email protected]> wrote:

> At half lease time, the client should request an address *renewal*. The
> renewal request would be sent to the DHCP server that provided the original
> lease, it is not broadcast to DHCPServer2.
>
> IIRC, it will not broadcast again until the lease actually expires.
> (someone will jump in to correct me if I'm wrong)
>
> Jeff
>
>
> On Fri, May 1, 2009 at 1:48 PM, Jim Dandy <[email protected]>wrote:
>
>> I've read some about the DHCP 80-20 rule but I'm not sure I really
>> understand it.  Here are two questions.
>>
>> 1) Why 80-20?  Why not 50-50?  If one server fails, wouldn't it be
>> better for the other server to have a larger range from which to
>> distribute addresses?
>>
>> 2) Let's say everything is working perfectly and both DHCP servers are
>> up.  Client1 requests an address and receives address 192.168.0.1 from
>> DHCPServer1.  Time passes until half of the lease time has expired so
>> Client1 requests an address.  This time DHCPServer2 is a little faster
>> and provides address 192.168.0.129.  DHCPserver1 doesn't know that a
>> different address has been assigned to Client1 so Client1 has an active
>> lease on both DHCP servers although only one of the addresses is
>> functional.  (Perhaps that's not what would happen?)  What happens to
>> DNS?  Are there now two entries in DNS (192.168.0.1 and 192.168.0.129)
>> for Client1?  For the purpose of answering this question, please assume
>> that I have Active Directory Integrated DNS on Server 2003 and DHCP on
>> Windows Server 2008.
>>
>> Thanks for your help.
>>
>> Curt Finley
>>
>> ~ Finally, powerful endpoint security that ISN'T a resource hog! ~
>> ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/>  ~
>>
>>
>

~ Finally, powerful endpoint security that ISN'T a resource hog! ~
~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/>  ~

Reply via email to