Change Class C IP Address to Class B Ip Address

Recently we have customer request to help them to merge the network from 3rd floor to 1st floor, because their company are merging together so that they want in the same network. Before that we have purpose them using firewall to plug in and do the routing and also can control the traffic but they strongly request they want make it on same network.
For the 1st floor now already facing IP insufficient to use issue,if now they merge together sure the have issue.So we are planning to help them change the network to class B private address , , .But I don’t know how the DHCP to handle those IP ?We can use Window server to create the scope to ,so that all the client able to get ip from …then go to then go to
Please advice = 3rd floor (DHCP server in Window Server) =  1st floor (DHCP server in router)
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Salah Eddine ELMRABETTechnical Lead Manager (Owner)Commented:

Simply disable the DHCP from one side (the router or the windows server), connect to both network and expend the number of host address for the network by configuring the mask so you will have the following:

Subnet ======>
First IP ======>
Last IP ======>
Broadcast ===>

Note that both IP and will be useful without errors

The fast step will be to keep the router as DHCP server with mask changing, but it will be complex to manage DHCP on it if the administrator get familiar with windows DHCP



Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
YaYangTeahAuthor Commented:
I don't understand for the DHCP part ,actually we plan to use window DHCP ,so in DHCP I just create the new scope first ip is and last ip is  ? If the IP so next distribution will automatically go to ?
Salah Eddine ELMRABETTechnical Lead Manager (Owner)Commented:

For DHCP part I prposed to keep it at router side since the scope is already which will need only the mask change and I mentioned that Windows DHCP will be easest to use!

So what you will need is to modify the current DHCP scope at windows or creat a new one the range will be - unless you have some reserved IP also you need to make sure you changed the mask on all staticaly defined nodes (routers, servers...)


Big Business Goals? Which KPIs Will Help You

The most successful MSPs rely on metrics – known as key performance indicators (KPIs) – for making informed decisions that help their businesses thrive, rather than just survive. This eBook provides an overview of the most important KPIs used by top MSPs.

Mohammed KhawajaManager - Infrastructure:  Information TechnologyCommented:
You create only one scope in DHCP if there is Ethernet run between the two floors.  In this case what you should do is change your IP network is to /23 or /22 which could give you 510 or 1022 hosts.  Create ether channel between the switches and now you have one network.  Next you create a DHCP scope ( or, change IP addresses on all devices that have static IP address and on your router (default gateway), select where you want to route Internet traffic to (I guess both floors have Internet connectivity).
YaYangTeahAuthor Commented:
Pretty good idea  just to change the subnet mask , this will reduce my job for the user site like all the printer mapping and network drive mapping.
Salah Eddine ELMRABETTechnical Lead Manager (Owner)Commented:
Good luck
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.