Windows Server DHCP -- superscope vs IP change ?

I currently have a 192.168.24.x
network that is running out of
IP addresses.

Someone recommended Option #2,
but I think Option #1 would
be a lot easier.

What option do you recommend on
Windows 2012 R2 Server and why ?
------------------------------------------------------------------------------------------------------------------------
Option #1
** add a 192.168.44.x network
** superscope 24.x and 44.x
------------------------------------------------------------------------------------------------------------------------
Option #2
** change to a 172.16.0.1 like
http://www.subnet-calculator.com/subnet.php?net_class=B
** change STATIC items
below on 200+ devices
** printers
** servers
** SAN's ISCSI connections
** VOIP phones
** wireless APs
** managed switches
** VPN tunnels at 3 sites
** contentFilter's staticIP clients
** C# custom APP code when moving COLO servers
** change DYNAMIC clients
** ipconfig /release & /renew



You didn't mention another fine option:Change from /24 to /23 i.e. 255.255.255.0 to 255.255.254.0.
You're lucky because 192.168.24.1 is the lowest address for both of them!
That will double the number of addresses.

No matter your gateway address, it can stay the same as can all static addresses. Only the subnet mask needs to be changed. This means that most network operations will continue to work even before making the subnet mask change.
The subnet mask can likely be changed on those computers / devices with with static addresses with a certain degree of leisure.

Everything getting addresses via DHCP can be changed with a refresh from the server.

I would start by changing the subnet mask on the DHCP server and the internet gateway and then the other static devices and then refresh the DHCP server leases - which will force all the other devices to change (quite painlessly).



You didn't mention another fine option:Change from /24 to /23 i.e. 255.255.255.0 to 255.255.254.0.
You're lucky because 192.168.24.1 is the lowest address for both of them!
That will double the number of addresses.

No matter your gateway address, it can stay the same as can all static addresses. Only the subnet mask needs to be changed. This means that most network operations will continue to work even before making the subnet mask change.
The subnet mask can likely be changed on those computers / devices with with static addresses with a certain degree of leisure.

Everything getting addresses via DHCP can be changed with a refresh from the server.

I would start by changing the subnet mask on the DHCP server and the internet gateway and then the other static devices and then refresh the DHCP server leases - which will force all the other devices to change (quite painlessly).



So basically just change STATIC subnet mask on the below on 200+ devices. allowing client's existing installed IP based printers to stay as-is on the client, no change needed since these are just installed by IP address, correct ?
** Windows DHCP server
** printers
** other servers
** SAN's ISCSI connections
** VOIP phones
** wireless APs
** managed switches
** VPN tunnels at 3 sites



I'd also opt to change your DHCP scope so that clients get an ip-address in the extended range, e.g. 192.168.25.1 - 200 ... This way you have the first range for everything network/server related.

And you could even make the subnet larger, so you have a large enough range for future growth, or divide the devices per range, e.g. Wireless AP's in 192.168,26.x and printers in another ... That's maybe a little overkill for now, but if you keep growing you only have to do this change (subnet) one time.



I don't know how many static addressed devices you have vs. DHCP "get an IP address automatically" devices you have.
So I'm not sure how to answer the question about 200 devices. That seems a lot for static (manually entered) addresses.

So first, DHCP:You change the DHCP server settings to reflect the new subnet mask and you extend the DHCP address range to something you want (i.e. bigger, more addresses).

Then, any devices with manually entered addresses:With the range I suggested, you can leave the IP addresses alone but you need to change the subnet mask.

And, the clients should not have to change any manually-entered IP addresses if they stay the same. That's correct.

Doing any of this suggests that there is some scheme for how you allocate addresses now and in the future (after this change). You don't want manually set devices to have addresses that overlap the DHCP range. Beyond that, it's a matter of preference. So, generally you'd have a DHCP range and what you view as a "static range" or "outside DHCP range" ... same thing. So for example:
If you have 192.168.24.1 for the gateway now and up to 192.168.24.49 reserved/used for manually-configured devices;
and, you have 192.168.24.50 - 192.168.24.254 for DHCPnow.
Then you might change this to:192.168.24.1 - 192.168.24.49 for manually-configured devices (or perhaps something larger depending on your projected needs).
and
192.168.24.50 - 192.168.25.240 for DHCP
Leaving 192.168.25.241-192.168.25.254 for other devices or static expansion.

It won't matter much if you move the DHCP range away from where it is now. i.e. that the new range doesn't include the current range at all. The impact of moving it vs. expanding it on top of what's being used now is that there could be static/dynamic overlaps if you have any static devices addressed within the NEW DHCP range. You'll still want to refresh the DHCP leases so that's not new/different.



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