Solved

Why would DHCP skip from 192.168.1.2 to 196.168.1.101?

Posted on 2006-07-14
5
652 Views
Last Modified: 2013-12-23
I restarted the router on a network as well as restarting the three PCs that were on that router. (there was no other router device involved)

All three pc's were running Windows XP.  All three PCs were set to "obtain an ip address automatically". They all did so from the same Netgear Rangemax Router, which had a gateway of 192.168.1.1

PC#1 was assigned 192.168.1.2.  But PC#2 was assigned 192.168.1.101. And PC#3 was was assigned 192.168.1.102 -- and she's still sleeping in MY bed! (sorry. "3 bears" joke)

I would expect them to be assigned similar IPs, e.g. x.x.1.2, x.x.1.3, and x.x.1.4  -- OR x.x.1.101, x.x.1.102, and x.x.1.103 -- in other words, the last octet ought to be simimlar -- EITHER in the single digits, or in the 100's -- for ALL THREE PC's -- right?

If so -- when it happens as it does above (odd mix), Anyone know why this happens?
0
Comment
Question by:dgrrr
5 Comments
 
LVL 57

Accepted Solution

by:
giltjr earned 65 total points
ID: 17112989
I would double check the DHCP scope (range) configured on router.  I would also check to see if PC#1 is really set to obtain IP address automatically.  It looks more like the DHCP scope starts at .101 and the first PC is statictly defined with .2.
0
 
LVL 37

Assisted Solution

by:Bing CISM / CISSP
Bing CISM / CISSP earned 35 total points
ID: 17113755
i am sorry that you can not actually control what pattern of IP address you obtained in a SPECIFIC address pool especially while the pool is larger. the particular IP that a DHCP enabled client computer may obtain depends on the algorithm of the DHCPing router.

it seems that you prefer some good-looking IPs on your computers, hehe. if so, since you have a few computers at home, you actually do not need such a big address pool, so just change the DHCP scope to a smaller one, for example, 192.168.0.2~6.

hope it helps,
bbao
0
 
LVL 87

Assisted Solution

by:rindi
rindi earned 25 total points
ID: 17114024
I'd also agree with gilt's explanation here. Maybe you originaly had to set that PC to a static IP in order to configure the router, after which you might not have set it back to get the address dynamicaly. In some case you can also set the dhcp server in routers to assign certain PC's with certain MAC addresses a specific IP. Taht is usually necessary when you are going to use this PC as a kind of server, maybe to be connected to from the internet to view webpages etc., or to connect to that PC from the inet remotely. In such a case you would probably also have set port forwarding to that ip inside the router. Such addresses are often assigned out of the automatic range.
0
 
LVL 8

Expert Comment

by:saw830
ID: 17127685
Hi,

I agree with what's been posted, but another thought has crossed my mind.  Is it possible that another DHCP server exists on your LAN?  Perhaps a Wireless Access Point or a PC with a dialup modem that has Internet Connection Sharing turned on, for example.  On the three PCs, open a command prompt (MSDOS) window and type IPCONFIG /ALL.  You should get a fairly large list of IP addresses configured for DNS, and Gateway, etc.  Partway down the list will be DHCP server, which is the address of the DHCP server that assigned the address information to your PC.  Compare with the other PCs and make sure that your PCs are getting assigned from the DHCP server that you think it is.

Alan
0
 

Author Comment

by:dgrrr
ID: 17158837
Saw830, There is only one server that I know of, but I will check.

Thanks to all -- I will check these when I go back.

I will assign points now. Thanks!
0

Featured Post

What Should I Do With This Threat Intelligence?

Are you wondering if you actually need threat intelligence? The answer is yes. We explain the basics for creating useful threat intelligence.

Join & Write a Comment

A brief overview to explain gateways, default gateways and static routes OR NO - you CANNOT have two default gateways on the same server, PC or other Windows-based network device. In simple terms a gateway is formed when a computer such as a serv…
Enterprise networks where VoIP phones have been deployed frequently use port configurations that allow both a computer and an IP phone to be plugged into the same switch port but use different VLANs. On Cisco equipment I'm referring to the "native V…
This demo shows you how to set up the containerized NetScaler CPX with NetScaler Management and Analytics System in a non-routable Mesos/Marathon environment for use with Micro-Services applications.
Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

757 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

20 Experts available now in Live!

Get 1:1 Help Now