How to Set Up Fault Tolerant SpectroSERVERs

Products

• DX NetOps
• CA Spectrum

Issue/Introduction

Fault Tolerance or high availability configuration is a redundancy configuration. It consists of Primary and Secondary SpectroSERVER. 

In case of the Primary SpectroSERVER down, OneClick Server switches to the Secondary SpectroSERVER automatically. With this configuration monitoring by Spectrum won't be interrupted when Primary SpectroSERVER is down.

Additional information can be found in the online documentation below.

   Establish Fault Tolerance

This document describes how to set up Fault-Tolerant SpectroSERVERs, as well as some points to consider when using a Fault-Tolerant environment.

Environment

DX NetOps Spectrum All Supported Releases

Component: SPCCSS - SpectroSERVER Core

Resolution

In a Fault-Tolerant configuration, two SpectroSERVERs are configured with the same landscape, but different precedence values, as shown below:

Server 1 (Primary):

LH=0x400000

Precedence=10

 

Server 1b (Secondary):

LH=0x400000

Precedence=20

 

Fault Tolerance can also be configured in a Distributed SpectroSERVER environment, as shown below:

Distributed Landscape	Master Landscape	Distributed Landscape
Server 2 (Primary): LH=0x600000 Precedence=10	Server 1 (Primary): LH=0x400000 Precedence=10	Server 3 (Primary): LH=0x800000 Precedence=10
Server 2b (Secondary): LH=0x600000 Precedence=20	Server 1b (Secondary): LH=0x400000 Precedence=20	Server 3b (Secondary): LH=0x800000 Precedence=20

In this example, the Master Landscape is the ONLY server to map the landscapes of the distributed servers. Each of these three servers knows about its respective secondary, and the Master Landscape knows about all six servers.

If the master landscape's primary server (Server 1) fails, the master secondary (Server 1b) leaves standby mode and becomes active. Servers 2 and 3 will automatically communicate with Server 1b. When Server 1 goes green again, all connections will be switched back to Server 1 from Server 1b and Server 1b will return to standby mode. 

The point to keep in mind is that Landscape handles MUST be different in a distributed environment (regardless of fault tolerance), and Precedence values MUST be different in a fault tolerant environment (regardless of distributing SERVERs).

Assuming that you have built a database on a Primary server and have installed SPECTRUM on your Secondary server, follow these steps to configure your Secondary server:

1. Do a database save on the Primary server, either with Online Backup or the  SSdbsave  from the command line (Offline Backup).
   
   
2. Move the saved file to the Secondary machine using FTP (make sure FTP is in binary mode) or SCP. Place the file in the  $SPECROOT/SS  directory on the secondary machine.
   
   
3. On the secondary machine, make sure the SpectroSERVER is NOT running, and then type the following command from your  $SPECROOT/SS  directory:
   
   ../SS-Tools/SSdbload -add 20 -il <filename>
   
   where <filename> is the name of the savefile you transferred from the primary server.
   
   
4. On the Primary server, bring up the Online Backup window and schedule daily Online Backups. Each time Online Backup runs, it will synchronize the databases of the Primary and Secondary servers.
   
   
5. Start the server on the Secondary machine.

Check the demo video.

 

 

Additional Information

The Secondary SERVER will not poll devices unless it loses contact with the Primary SERVER. If you want the Secondary to continually poll all models (thereby making it a hot stand-by instead of a warm stand-by), you need to add the following line to the  $SPECROOT/SS/.vnmrc  file on your Primary SpectroSERVER:

secondary_polling=yes

For further information:

Setting Up Processes in a Fault-Tolerant Environment

You tube demo video