Within each management site, you can explicitly designate a primary management server and a backup, or secondary management server for each agent computer. Establishing a primary and secondary management server for each agent computer provides the following benefits:
Predictable failover support
For information about how failover works, see How Failover Works.
Static load distribution
For information about how load distribution works, see Distributing Processing Load.
You can designate the primary and secondary management server when you install the AppManager agent. You can also run the AMAdmin_SetPrimaryMS Knowledge Script for Windows computers and the AMAdminUNIX_SetPrimaryMS Knowledge Script for UNIX computers after installation.
After you explicitly designate a primary management server, only the primary management server sends job requests to the agent and receives corresponding events and data. If communication with the primary management server is interrupted and you have identified a secondary or backup management server, communication is automatically transferred to the secondary management server. If you have not specified a secondary management server, data and events are stored locally on the agent computer. When communication with the primary management server is restored, the agent then resumes communication with the management server.
NOTE:For UNIX agents, the management server you identify during installation becomes your default primary management server. The installation steps also prompt you to specify whether the UNIX agent can also communicate with other management servers. You can then run the AMAdminUNIX_SetPrimaryMS Knowledge Script to designate a secondary management server.
If you have multiple management servers in your environment, NetIQ Corporation recommends the following:
Designate the local management server as the primary management server. For more information, see Designating the Local Management Server as the Primary Management Server.
Configure a single management server for remote installation tasks. This configuration avoids excessive network traffic associated with remote agent installation or upgrade tasks.
Designate primary and secondary management servers for all agent computers. For more information, see Configuring a Primary and Secondary Management Server for Agent Computers.
When you install the management server component, an AppManager agent is automatically installed locally on the management server. Configure the local agent to have the local management server designated as its primary management server.
To designate the primary management server for the agent on the management server:
Log on to the Control Center console as a user who has permissions to run Knowledge Scripts.
If you have not already done so, run the Discovery_NT Knowledge Script and any additional Discovery Knowledge Scripts on each management server. For example, if you have installed the management server component on the computer JUNO, drag and drop the Discovery_NT Knowledge Script onto JUNO in the Enterprise Layout view of the Navigation pane.
After a successful discovery, run the SetPrimaryMS Knowledge Script on the management server.
On the Values tab, specify the local management server as the primary management server. You do not need to configure a secondary management server.
Each agent computer can have only one designated primary management server and one designated secondary management server. Unless you designate the primary and secondary management server during agent installation, perform this task manually after you:
Configure each management server to be its own primary management server
Configure a single management server to perform remote installation‑related tasks
To designate a primary and secondary management server for each agent computer:
Log on to the Control Center console with an account that is a member of the Administrator user group.
Ensure that all agent computers have been discovered.
Run the AMAdmin_SetPrimaryMS or AMAdminUNIX_SetPrimary MS Knowledge Script on the agent computer.
On the Values tab, specify the primary and secondary management servers for this computer.
(Conditional) For Windows agents, set the management server operation to perform to designate both the primary and secondary management server for this agent computer, and then click OK.
(Conditional) For UNIX agents, select either Set Primary management server or Set secondary management server to designate a new primary or secondary management server for this agent computer, and then click OK.
To change both the primary and secondary management server, run the Knowledge Script twice. By default, if you use the script to specify a new primary management server, the management server that you specified when you installed the agent becomes the secondary management server. Use the Unset specified management server option to remove a management server you no longer want to use.
It can take up to 15 minutes for the QDB to designate the primary and secondary management servers. To start new jobs after you change the designation for an agent computer, wait until the repository updates the management server designation.
Once the management server designation is complete, you can run jobs on the agent computer. The designated primary management server sends job requests.
After you designate a primary and secondary management server for an agent computer, the QDB and the local repository on the agent store the server information. The agent accepts job requests from and sends events and data to its primary management server.
If an attempt to communicate with the primary management server fails, the agent waits for one minute before attempting to reconnect to the primary management server. By default, the agent attempts to connect three times every minute before failing over to the secondary management server.
After the third attempt to connect to the primary management server fails, the agent sends events and data to the secondary management server to store in the QDB. However, the secondary management server does not immediately send new or changed job requests to the agent computer.
Every 15 minutes, the management server updates its list of agent computers. If a secondary management server picks up communication with new agent computers because communication with a primary management server fails, the secondary management server updates itself with that information after the interval. If there are new jobs or changes to job properties, the secondary management server can then communicate the changes to the agent computers that failed over. Because of this delay before the secondary management server recognizes the failed-over agent computer, it can take up to 15 minutes to communicate job information to the agent computer.
While the secondary management server manages the agent computer, the agent continues trying to contact its primary management server every minute. After the agent re-establishes communication with the primary management server, the agent sends events and data to its primary management server. Each management server updates its list of agent computers and the communication of job information transfers back to the primary management server one minute later.
For information about modifying the interval and the number of times the agent attempts to contact the primary management server, see Changing Agent Failover Configuration.
For information about changing the interval at which a management server checks its list of agent computers, see Changing the Polling Interval for Agent Computers.
You can distribute processing load by assigning agent computers to different management servers. For example, you can assign agent computers in New Zealand to a management server in New Zealand and agent computers in Sweden to a management server in Sweden. Or you can assign agent computers to management servers according to functional groups or departments.
If you plan to use multiple management servers to balance processing load, limit the number of computers each management server is responsible for monitoring. For example, if you have two management servers, LONDON and PARIS, configure half of your agent computers to use the LONDON management server as the primary management server and PARIS as the secondary management server, and half of your agent computers to use PARIS as the primary management server and LONDON as the secondary management server. The primary/secondary pair should not manage more than approximately 600 agent computers between them, which means each management server can manage up to 300 agent computers. This configuration ensures that no single management server is responsible for more agent computers than it can handle in the event of a failover.
You can verify whether a management server that is assigned to an agent computer is the primary management server or the secondary management server.
To verify the management server assigned to an agent computer:
In the Control Center console, click the agent computer in the Enterprise Layout view of the Navigation pane.
The view pane displays the primary and any secondary management server for the agent computer.
In some cases, you might want to change the management server assigned to an agent computer. For example, the management server might not be performing as expected or an agent computer might move to another network or geographical location. For more information about changing the management server, see Configuring a Primary and Secondary Management Server for Agent Computers.
You might want to add new management servers to your AppManager management site. Before adding a new management server, determine whether to use the new management server as a passive, secondary management server for all agent computers or as a primary management server for some of your agent computers.
If you plan to use the new management server as a primary management server for some agent computers to balance processing load, plan to configure 50% of the agent computers to use the first management server as the primary and to use the new management server as the secondary, and configure 50% of the agent computers to use the new management server as the primary and to use the first management server as the secondary.
To add a management server to your management site:
If you have not explicitly designated the management server for every agent computer, run the AMAdmin_SetPrimaryMS or AMAdminUNIX_SetPrimaryMS Knowledge Script on the agent computers to configure the current management server as the primary management server.
Install the new management server and configure it to communicate with the QDB.
Run AMAdmin_SetPrimaryMS or AMAdminUNIX_SetPrimaryMS on the new management server computer and designate the local management server as the primary management server for the local agent. For more information, see Designating the Local Management Server as the Primary Management Server.
Run AMAdmin_SetPrimaryMS or AMAdminUNIX_SetPrimaryMS to configure each agent computer to recognize the new management server.
It can take up to 15 minutes for the management server to identify changes to its list of agent computers. The agent computer can send information to a newly-designated management server immediately, but there might be a delay of approximately 15 minutes before a newly-designated management server sends new job information to the agent computer.