In order to manage IP Addresses with the build in IPAM in the IT-Assets Management Database / CMDB, you will need to create VLANs and their respective IP-Scope.

VLAN numbering

VLANs are numeric, while there is a restriction on how many VLANs you can have from a switch perspective, there is no numeric restriction here other then those of the datatype INT (-2^31 (-2,147,483,648) to 2^31-1 (2,147,483,647)).

Normally you should only have one IP scope per VLAN, as the whole purpose is to avoid collision domains and other downsides of multiple IP scopes within the same VLAN. If you really need a second IP scope you could use a prefix in the VLAN number like 100,000 or similar, so make it clear it is a secondary scope in an existing VLAN.

If you do not use VLANS at all, you can just use any number per IP scope needed.

VLAN Name and IP scope

Provide a name and description for the new VLAN so you can quickly identify it. The description could include hints for the default gateway and other settings, in order to make it easier down the road.

The IP scope is provided in a CIDR notation, meaning something like for an IP network with 24 bit ( If you are unsure, don’t worry – the IT Assets Database application shows you right away the results of your IP CIDR notation, if it is calculatable at all. You can see the subnet mask and CIDR notation as well as the complete size of the IP scope and how many usable IP addresses you would have. Besides this you see the first and last IP address within the defined scope.

Once you have entered the IP CIDR notation you need, click on the generate button. This button is only available if the IP addresses for this VLAN have not yet been generated. It will create all IP addresses for this IP scope / VLAN so you can use them and assign them using the IP Addresses module.

Available fields and references