DHCP leaves low

[DotNetNewbie]

Hi there,

We have a single DHCP range (191.9.212.x / 255.255.255.0), like most we have a small amount excluded for printers, routers, servers etc.

However a new project that is due to be launched required 15 static IP addresses. This will leave us very low on usable addresses and on busy days could mean we run out.

We have lowered the lease time to make sure the maximum amount of IP addresses are available. However we are considering adding a second range to the server. Though it is my understanding we will need a switch that can do layer3 to achieve this.

Can this be done without adding the extra layer?

Any ideas most welcome.

FB

 

[itsp1965]

I assume the 191.x IP subnet has been given to you by your service provider. With the lack of IPV4 addresses, it would be really difficult to expand an existing public address space (and don't attempt to increase it yourself as you might conflict with other public networks). You may want to consider implementing NATing in your network which will allow you to have a network consisting of private addresses and leave your 191.x addresses for external services (web server, DNS, e-mail, etc)

 

[DotNetNewbie]

Hi,

Its an internal range of IP addresses, I inherited the set up when they gave me responsibility for the network. I would love to change it but with everything so embedded with the addresses I am sure it would cause me more trouble than its worth

 

[kmcferrin]

with everything so embedded with the addresses I am sure it would cause me more trouble than its worth

That depends. If anyone ever tries to access and external service at something in that 191.x range then they won't be able to get to it because your routers will believe that it is local.

The best solution will be to add a second range of IP addresses and get a layer 3 device (router, switch, server running RRAS, etc) to handle routing between the two subnets. When you do that, change the scope used for your existing subnet to use a proper private address range (192.168.x.x, for example). This is an excellent opportunity to fix a current problem and correct the mistakes of the past.

________________________________________
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[58sniper]

I would love to change it but with everything so embedded with the addresses I am sure it would cause me more trouble than its worth

It's not that bad with proper planning. I've done it when I've gone into similar environments.

If you're going to create another subnet, consider putting your servers and related infrastructure on their own subnet.

Again, proper planning should be 90% of the work.

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