Re: IP conflict in my network

I dont know if i fully agree with the lease running out while the
machines are turned off

If a lease was to run out while a pc was turned off and then
consequently this lease was given to another computer, the original
computer when it is turned on should be requesting a new lease as it
knows that its lease has run out

Below is a url to dhcp guide

http://www.tcpipguide.com/free/t_DHCPLeasesLeaseLengthPoliciesandManagement-3.htm

It is still obviously a good idea to work out a good lease time that
suits your needs but the dhcp server should handle the machines leases
running out while turned off without problems

I would be looking to see that you dont have any pcs or printers or any
other devices with static ip addresses and, if you are still having
problems i would look at your pool of addresses and see if it is big
enough for all your pcs and devices

Also I would check to see that you dont have 2 devices setup for dhcp,
ie if you have a broadband modem/router it would most likely be by
default setup for dhcp.

Spender wrote:
On 5 Dec 2006 02:21:31 -0800, "suad" <suad@xxxxxxxxxx> wrote:

some users have IP conflict. Ip address are destrubuited dynamicaly
by DHCP. why these users have this problem in my netwrok. do u think a
virous cause this problem. how can I prevent it.

Virus? Why does everyone think everything is caused by a virus? Most
computer problems are caused by Microsoft, not viruses. Oh well.

A problem like this can be caused by the IP address lease running out, as
far as the DHCP server is concerned, while the system that owns the lease
is turned off. The DHCP server then hands out that IP to another system.
The first system is then turned on, and bing, bang, boom you have an IP
address conflict.

Check the DHCP server and extend the length of the IP address lease
lifetime. Chances are it is too short for your needs. Then do an "ipconfig
/release" on all systems, followed by an "ipconfig /renew".

.

Relevant Pages

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