Licensing Model
NCache Enterprise Edition uses logical processor based licensing for Windows platform and Virtual Machines.
The minimum number of licenses required is 2, whether the machine has 1 logical processor or 8. However after 8 logical processors, the number of licenses is incremented by every 4 logical processors added. For example, for 9-12 logical processor machine, licenses required increments to 3. For 13-16 logical processors, 4 licenses are required and so on.
| Number of logical processors detected | Number of licenses required |
|---|---|
| 1-8 | 2 |
| 9-12 | 3 |
| 13-16 | 4 |
| 16-20 | 5 |
Important
NCache allows unlimited licenses on a single machine, based on the logical processor count.
However, in case you increase the number of your logical processors to a number where the requirement for an additional license becomes valid, you get a friendly warning (can be viewed through Event Viewer tool in Windows) that you need to reactivate your license as your logical processor count has exceeded its range limit. After a 15 day interval your caches stop working if reactivation does not take place.
NCache provides Server and Client licenses. A sever license activates the server machine whereas the client license activates the client machines. Based on these licenses there are two licensing schemes provided by NCache.
1. Client Server Licensing
2. Server Activated Licensing
These licensing schemes can use either Perpetual or Subscription based licensing model which is explained below later.
Client Server License
Client Server license activates your client and server machines based on the license activation key. At the time of purchasing the license key, you need to specify the number of server as well client machines to be activated and the provided key will activate your clients and servers. This licensing scheme is known as client-server licensing.
Server Activated License
The number of Server and Client licenses required in this model is exactly same as in Client-Server License model. This type of licensing scheme is useful when users have no physical access to activate the all the client machines. For example in cloud or containerized environments, users may not always have the access to activate the client machines where their applications are running. Similarly, physically activating a container instance or cloud VM instance does not make sense if that instance is used temporarily. For example, when users scale down the application tier, they’ll stop a few instances of containers or cloud VMs. And when they scale back up, the new instances can possibly be run on a new hardware. Therefore, in this licensing model, cache servers issue licenses to clients when they connect to cache servers.
In this licensing model, following is some extra information required during the activation of cache servers.
Environment
Nodes participating in cache cluster must be activated with the same environment name e.g Production, Staging, Testing etc. These environment names must be finalized at the time of purchasing licenses. License keys are issued for the environment names given by customer. Cache servers cannot be activated for environment names not associated with the license key.
Number of Client Licenses
Since in this licensing model, clients are not physically activated, cache servers issue the required number of licenses to clients at the time of initialization. Therefore, while activating cache servers, the number of client licenses that this cache server can issue are also specified. Whenever a new unlicensed client connects to this server, server issues it a license based on the number of logical processors of that client. A cache server cannot issue client licenses more than the number it is activated for. The number of client licenses can be increased or decreased based on the needs by reactivating cache servers with desired amount of client licenses. In one cache cluster, the number of client licenses provided must be same for healthy communication.
Types of Licensing Models
NCache provides two kinds of licensing models:
Perpetual License
A perpetual license provides the user with the right to buy a license for an indefinite amount of time which means the user does not need to re-new the license unless new logical processors are added. Let’s suppose you were using NCache with 8 logical processors and increase the logical processor number to 9. NCache will not stop working for 15 days and you will get a warning for reactivation. However, after 15 days, caches will stop working.
Subscription Based Licensing
NCache Subscription based licensing model requires to pay an annual fee by the customer for a specific period. The subscription can be purchased by the user for a time period of 1 year to the maximum of 5 years. The user can activate his license once the subscription is bought by the user. The license activation scheme is same for NCache server as well as client.
This subscription must be renewed at the end of the subscription period. Otherwise all the running caches will be stopped after a 30 day grace period post expiry provided by NCache.
For this, you have to reactivate your NCache License through PowerShell cmdlet Register-NCache for Windows or through activation script for Linux.