How to scale AccAD CFE

[Former Member]

Document Title:  How to scale AccAD CFE.
Author: Girish K. Garje
Date: 27th Feb 2015.

1. Introduction:
Once installation of AccAD SFE & CFE is completed then it is important to review the necessity to scale if the no. of users or services delivered increase over the period of time. This document basically covers the procedure to scale the AccAD Client Front End part i.e. CFE.

2. Purpose:
  As we know AccAD is to boost the performance of web applications accessed across the globe. However there is limitation on no. of parallel/concurrent users accessing the application through AccAD. The slot-0 instance which is installed by default after installing the CFE instance has limited no. of threads. Hence even though there is enough hardware capacity i.e. RAM, CPU & storage etc, then also the CFE would not be able to handle more user load.
There is a quick and easy way to scale the CFE instance to manager the concurrent users. i.e. to add CFE slot-n instances on existing CFE server. This way CFE can have additional threads on CFE server.

3. Overview
  At high level adding the CFE instance contains below activities. While adding new slot CFE instance on same server, It is critical to do the sizing exercise. Once we the server has been configured to have required hardware i.e. RAM, CPU storage etc, then Create another CFE instance on SFE end for same location by giving all the parameters with change in listener port.   We export the configuration xml file from SFE & import it at CFE end. Post this the proxy team should carry out adjustments to include the additional CFE slot instance.

4. CFE Sizing:
Below information is necessary to estimate hardware requirement for 2nd CFE slot instances on same server,
4.1 No. of concurrent users e.g.  Let’s consider 400 concurrent users.
4.2 No. of services delivered to CFE e.g. Let’s consider 30 services
4.3 How many SFE slots to be installed. Let’s consider 1 additional slot i.e. total 2

4.4 RAM Calculation

The formula for RAM calculation is as follows
= n * (500MB + 80MB * (# services delivered to the CFE))
= 2 * (500MB + 80MB * 30)
= 2 * 2400 MB
= 4800 MB
Approx. = 5GB

4.5 CPU
As rule of thumb: 1 CPU - 300 concurrent users 
For 400 concurrent users 2 Cores.

A reference hardware requirement for 400 concurrent users can be as follows

	CFE
	Recommended
CPU	2 Core
RAM	5 GB
Hard Disk	150 GB

Now compare the existing and recommended hardware parameters and get it upgraded as required from the hardware team.

5. Adding CFE slot-1 instance
5.1 Login to SFE UI using admin user password.
5.2 Navigate to Appliance Landscape Tab --> Expand the Appliance Landscape tree --> Appliances --> Select & expand the Location of CFE for which we have to add the additional CFE slot instance
5.3 Expand Engine --> Expand Instances. Here we observe the already existing CFE slot instance number.

5.4 Once we click on Instances then we see option on right side of the page to create a New Instance and field appears which allows you to enter the Appliance ID.  Enter the new Appliance ID which should be unique. Click on Create button

5.5 Enter the details in the fields as per below form. Here we maintain the SFE IP & port details.

Few changes between old CFE slot instance and this new slot instance is the

5.5.1 Proxy listening port.
e.g.
slot-0 : 18080
slot-1: 18180.

5.5.2 Web Proxy Autodiscovery Listening Port
e.g.
slot-0 : 18083
slot-1: 18183

5.5.3 Listening port
e.g.
slot-0 : 1600
slot-1: 1601

5.6 Once all the fields are entered click On Save Button
5.7 Click on Apply Button.
5.8 This shall make the changes at SFE level.

6. Exporting the Appliance
Now Expand on the Appliance tree node on left side and select Name of Appliance on which we have recently added the CFE slot-1 instance. On the right side it gives option to export the Configuration xml file for this particular appliance. Click on Export button.

 

7.  Importing the Config xml in CFE
7.1 Login to the respective CFE UI using admin user & password.
7.2 Navigate to Local Configuration tab --> Click on Appliance node.
Click on the Import button on the right side of the page

Browse the dialog box and select the Config xml file which we had exported from SFE.

7.3 Click on Save
7.4 Click on Apply button.
7.5 Restart the adui process of CFE at OS level using command     service adui restart
7.6 Now if we login to CFE UI again it shows 2 CFE slot instances  as follows