help please, dhcp networking question

Hi There

I am a little confused and was hoping someone could explain something to me, we are running out of ip addresses. So i want to create vlans moving forward but how will the new ip range be setup currently it is a /24 subnet. my question might be a bit stupid of not clear but im new to networking.


2 Comments   [ + ] Show comments
  • A little more detail of the makeup of your network would be helpful.
    1. What is providing your DHCP scopes, server or other device?
    2. Are your switching devices capable of multiple VLANs?
    3. What will provide the routing and can it route to different VLANs?

    I'm sure people would argue here but would it not be easier to modify your existing subnet to a /23 and give your scope a greater pool of addresses. - Druis 6 years ago
  • I agree with the suggestion of using a /23 ( subnet. I've been using that for years and it's works with all of the hardware and software I currently support (years ago I saw some items that wouldn't allow it). To supernet two class C subnets, you'll need to change the third octet, which will need to start with an even number (not odd one). i.e. and, not and

    If you're using DHCP, you may need to delete the scope and recreate it. If you do that, I'd suggest changing the old lease time to something pretty short, maybe 10 minutes, and make sure all of the devices get that new lease time before removing the old scope. Then when the new scope is created, the devices will get a new address quickly. It's may be better if you can turn off as many DHCP devices as you can before deleting the old scope. - PaulGibson 6 years ago

Answers (0)

Be the first to answer this question

Don't be a Stranger!

Sign up today to participate, stay informed, earn points and establish a reputation for yourself!

Sign up! or login


This website uses cookies. By continuing to use this site and/or clicking the "Accept" button you are providing consent Quest Software and its affiliates do NOT sell the Personal Data you provide to us either when you register on our websites or when you do business with us. For more information about our Privacy Policy and our data protection efforts, please visit GDPR-HQ