There are some great features in EfficientIP’s SOLIDserver product that not many people know about. One of these gems is the customisation available via the class studio.
Class studio enables the creation of many custom fields in numerous locations throughout the UI and the behaviour of these fields can be altered dependent upon other settings. While the class studio provides an incredible amount of flexibility, some of its more interesting features remain hidden, so I thought it might be useful to write a post about a little known feature that is the “$is_terminal” variable.
When defining subnets within the IPAM module of SOLIDserver, there is the concept of “imbricated” and “terminal” subnets. You can think of an “imbricated” subnet as simply being a “container” that contains smaller or “lower level” subnets within an address space hierarchy. Another way of thinking about it is may be as an IGRP/EIGRP summarisation.
A “terminal” subnet on the other hand is at the bottom of the address space hierarchy and is the subnet that contains the individual IP addresses. As it is at the bottom of the hierarchy it terminates that part of the tree, hence “terminal” subnet.
When defining subnets in SOLIDserver, you can specify whether they are terminal subnets or not via a simple tick box. But what anyone who has used the class studio might not realise is that if you have any custom fields (e.g. VLAN_ID), you can turn the display of these fields on or off simply by checking if the “terminal” tick box is checked or not.
As an example, let’s look at a couple of screenshots of a subnet addition page:
What we can see is that when “terminal subnet” is ticked or unticked, various standard fields are displayed or hidden, such as “gateway”, “number of pool” etc., but custom fields may not exhibit this behaviour. In our example above, regardless of whether “terminal subnet” is ticked or not, the “VLAN ID” field is continuously displayed. What if we only want to display the VLAN ID if it is a terminal subnet? We can use the class studio to modify the subnet class to hide the VLAN ID field, preceding comment and the green separator if the “terminal subnet” check box is NOT ticked (or if it is unticked).
First let’s look at the subnet class in class studio:
If we click on “vlan_id_demo” we can adjust the properties of this field by adding “$is_terminal” into the “Show if…” box:
Setting this variable is the secret to determining if this field will be displayed or not. By setting “Show if…” to $is_terminal we are simply saying display this field if the terminal subnet tick box is checked (i.e. if $is_terminal is true).
We now need to do the same for the comment and horizontal line that prefixes and suffixes this field:
With the “Show if…” field set, now when we untick the “terminal subnet” tick box, the VLAN ID field disappears along with the comment and horizontal line:
I am great believer in simplifying things and removing superfluous fields that may not be required in certain circumstances. Fewer fields = less chance of operator error and more efficient data entry. The company that produces SOLIDserver is called EfficientIP after all! 
The post Using the “$is_terminal” variable in SOLIDserver class studio appeared first on DNS, DHCP, IPAM (IP Address Management) | BYOD, NAC | Calleva Networks.