Go Premium for a chance to win a PS4. Enter to Win

x
?
Solved

Add additional IP network

Posted on 2008-09-29
3
Medium Priority
?
203 Views
Last Modified: 2010-04-02
I have a 10.1.1.0 network, i have the need to have another such as 10.1.2.0, can I simply change my subnet mask from 255.255.255.0 to 255.255.0.0 and the two networks will talk?

Also where all do i have to change the subnet mask?  router, firewall, swithes, dhcp server?
0
Comment
Question by:jrri
  • 2
3 Comments
 
LVL 58

Expert Comment

by:tigermatt
ID: 22599016
Yes. A bitmask of 255.255.0.0 will be more than ample to get those two networks to talk.

The subnet mask needs to be changed everywhere. Anything which has a static IP address needs the bitmask changing, and you can then update it in the DHCP Server scope so that dynamically assigned clients pull the new bitmask through DHCP automatically.

-tigermatt
0
 
LVL 1

Author Comment

by:jrri
ID: 22599082
Are there any issues that may bite me or is it prett clean?

Mike
0
 
LVL 58

Accepted Solution

by:
tigermatt earned 1400 total points
ID: 22599887
The only potential issues are the actual switch over stage from the old bitmask to the new bitmask. Your servers will obviously need a restart before they will re-register and communicate with each other again.

You do have an alternative. You can keep both networks with a subnet of 255.255.255.0, but configure the router with a different subnet. This technique is known as Variable Length Subnet Masking (VLSM) and it is quite common on larger networks. I am using it here at home right at this point in time.

Essentially you keep both subnets as 255.255.255.0 as I already said, but set the router to something like 255.255.0.0 as the bitmask. This means the router can then communicate across both the networks. The only difference is any traffic destined for the 10.1.2.0 network would need to pass through the router, but I consider this a minor inconvenience compared with doing a bitmask change across your whole site.

Each subnet will appear as a different subnet in its entirety. Netbios Browsing, for example, will not work, because it is restricted to a specified subnet. That is the only other downside I can think of to this approach.

-tigermatt
0

Featured Post

Vote for the Most Valuable Expert

It’s time to recognize experts that go above and beyond with helpful solutions and engagement on site. Choose from the top experts in the Hall of Fame or on the right rail of your favorite topic page. Look for the blue “Nominate” button on their profile to vote.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article explains the fundamentals of industrial networking which ultimately is the backbone network which is providing communications for process devices like robots and other not so interesting stuff.
Tech spooks aren't just for those who are tech savvy, it also happens to those of us running a business. Check out the top tech spooks for business owners.
Here's a very brief overview of the methods PRTG Network Monitor (https://www.paessler.com/prtg) offers for monitoring bandwidth, to help you decide which methods you´d like to investigate in more detail.  The methods are covered in more detail in o…
Monitoring a network: how to monitor network services and why? Michael Kulchisky, MCSE, MCSA, MCP, VTSP, VSP, CCSP outlines the philosophy behind service monitoring and why a handshake validation is critical in network monitoring. Software utilized …

877 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