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New Member

supernet

I currently have the addressing scheme set 192.168.100.0/24

and I am running out of addresses so I am going to change to 192.168.0.0/16

only have 1 gateway

before I can get to every single machine to change them all some will be on one scheme and the rest on the other

my question is..can I setup the router to recognize both until all are on the same address scheme?

and afterwords will i need to change the router's mask?

7 REPLIES
Gold

Re: supernet

first thing: make sure you have ip classless in the router.

if you only have one subnet, that should do it.

Anonymous
N/A

Re: supernet

yes ip classless is in

ok so everyone's default gateway will stay the same and no changes need to be made on the router..

all i need to do is change everyone's subnet mask to

255.255.0.0 instead of 255.255.255.0 and the ones that get upgraded before the old ones will still communicate ok?

thanks

New Member

Re: supernet

If you need to separate these networks in the future, the /16 mask is not going to serve you. Why do not you use a supernet of 23 bits instead which give you 508 hosts per net, and still permits you to use other networks with the prefix...??...Rgds

New Member

Re: supernet

Or why not migrate to a 10.0.0.0 range that way you could define a secondary adres on an interface and communicate with all other hosts trough out the migration.

Re: supernet

Hi,

I think you need to change the subnet mask on your router FIRST. Otherwise the upgraded PCs will loose their connetions to other networks.

But I agree with Tsasbrink that the easier way is to move to a new address range (10.0.0.0, e.g) using secondary adres on the router interface. Changing only the subnet mask on your PCs means a high risk of some forgotten ones with the old mask left.

Regards,

Milan

Anonymous
N/A

Re: supernet

great thanks I will try the new address range

as long as I can have the old static ones and the new 10.0.0.0 addresses communicate with each other

that would work as a econdary address or would I have to create a vlan?

thanks again

Re: supernet

Hi,

you don't need to create a new VLAN.

Secondary address can be used to enable the readdressing process:

You can leave all the PCs in the current VLAN and change the IP addresses to the new address range (secondary) per PC (don't forget to change the default gateway address to the secondary address on the new addressed PCs).

The old ones will still see each other, the new ones will see each other.

The old ones will see the new ones BUT their connection will be ROUTED. So you can notice Microsoft neighborhood or other broadcast-based communication broken between the old and new PCs.

On the other side the IP broadcasts from old PCs will bother the new ones (all in one VLAN) but they will not be able to accept them (another subnet). This is why secondary address should be used only as a temporary solution.

Finally, you should remove the old address from your router interface.

HTH,

Milan

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