keep the same segment number or change it to different one?

[Hanry Zhou]

The company is planing to migrade a large application environment which is consiists of a number of hpux server, and also client window servers. All invovled servers, backups, and clients, as well as some storages will be migraded to new hardwares. so, the question is, should we keep the same major segement number, for instance "212" or a new different segment "216"?

Thanks for your advises.

[Matti_Kurkela]

Segment number? Is this related to IP addresses?

Your question should probably be asked from someone who knows the large application and understands its requirements.

Does the application configuration include IP addresses or just DNS names? If only DNS names are used in the application configuration, migrating the application to a different IP segment should be just a matter of updating the DNS names so that the application components will find each other in new IPs using the old names. But if IP addresses are used in the application configuration, you will need to go through all the application configuration settings to find the old IPs and replace them with the appropriate new IPs.

If the application licensing is tied to IP addresses (i.e. the application will run only if it has a license file that matches the IP address(es) it's running in), changing the addresses means you'll need to update the licenses too.  That means contacting the application vendor and asking them to create new license files for you. The vendor might require a fee for this support service, or some proof that the use of the old IP addresses will actually be stopped. If the vendor is no longer in business, or will not support your version of the application any more, you will be stuck with your existing licenses.

If you are migrating the application to a different network segment, you will also need to consider network connectivity and firewalls. Can the users of the application reach the application servers in their new locations? Do you need firewall configuration changes to make it work? You'll need someone who understands your network to answer these questions.

If all this is already known... then consider the history of this application environment, and try to predict the future. Is it likely that the environment might need to be expanded? If yes, then using a new segment might allow you to reserve some IP addresses for future expansion.

[Laurent Menase]

Hi

Everything looks to be a matter of need.

Do you plan to change your netmask from 255.255.252.0 to 255.255.248.0?

and move system from range X.X.212.x  to X.X.215.x to range

X.X.216.X to X.X.223.X ?

If range X.X.208.X to X.X.211.X is available, probably even better moving to 208

with netmask 255.255.248.0 hence no need to change system IP addresses, only new system would be in the new range.

It is clearly an operational decision, and capacity planing

But I am not sure I understood the question