6 Oracle Traffic Director
Oracle Traffic Director (Traffic Director) is a software-level load balancer, used to load-balance incoming HTTP connections among origin-servers (host:port pair) that host the actual content.
Traffic Director has the following functions:
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Reverse Proxy—Distributes incoming traffic among servers using load-balancing algorithms. The forwarding mechanism is based on URI and on handling sessions.
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Proxy Caching—Stores frequently accessed html pages.
You can use the Traffic Director to create a configuration that involves defining virtual-servers, listeners, origin-servers, and server-pools. This configuration is then deployed on a set of hosts. The instances of the same configuration form a configuration.
Note: In a High Availability configuration (Active-Passive or Active-Active), Oracle Traffic Director supports only 2 OTD instances for a given configuration. Hence, Enterprise Manager Cloud Control 12.1.0.3 and higher monitoring capability is limited to at most 2 OTD instances for a given OTD configuration.
The virtual-server is the main component that is configured with the load-balancing properties, for example, the servers to distribute traffic to (origin-servers and pools) to use, the IP-address and port on which to listen for requests (listener), and so on.
Hence, the typical hierarchy of a Traffic Director deployment is that of a Traffic Director configuration consisting of a set of instances deployed on hosts, and each instance has components like virtual-server, listener, proxy-cache along with origin-servers and origin-server-pools.
Following is the target list:
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Traffic Director Configuration
The Traffic Director Configuration target contains configuration and performance metrics pertaining to components like virtual-server, proxy-cache, tcp-proxy, origin-servers and server-pools, at the configuration-level.
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Traffic Director Instance
The Traffic Director Instance has performance metrics for the same components but at the instance level.
Traffic Director Instance target is used to monitor one instance of a Traffic Director Configuration running on a host. This target shows the performance information of the Instance running on that host.
Use the following sections in this chapter to learn more about Traffic Director.
For additional information, see Oracle Traffic Director Administrator's Guide.
Before Discovering Traffic Director 11g
Before you discover Traffic Director, you need to configure Traffic Director instances for SNMP monitoring and start the SNMP subagent.
See the Monitoring Using SNMP chapter in the Oracle Traffic Director Administrator’s guide. In particular, perform the steps described in the following sections:
- Configuring Oracle Traffic Director Instances for SNMP Support
- Configuring the SNMP Subagent
- Starting and Stopping the SNMP Subagent
Note:
Discovering Oracle Traffic Director 12c is automatically performed as part of Oracle WebLogic Domain discovery. For more information on adding a domain to Cloud Control, see Discovering and Adding WebLogic Domains in the Oracle Enterprise Manager Cloud Control Administrator's Guide.
Adding a Traffic Director to an Exalogic Target
To manually add the Traffic Director dashboard to an Exalogic target, perform the following steps:
- From Enterprise Manager, select Exalogic from the Targets menu.
- Click the link of the name of the Exalogic Elastic Cloud to which you want to add the Traffic Director dashboard.
- On the Exalogic Elastic Cloud page, click the Software tab.
- On the SYSMAN icon located at the top right of the page, select Personalize Page.
- On the Editing Page, click Add Content. On the Add Content popup, move to the Traffic Director item and click the associated Add link. Click Close.
- On the Editing page, click Close.
The Traffic Director region is now visible from the Exalogic Elastic Cloud dashboard (Software tab).
About Traffic Director Configuration
A configuration is used to create a configuration of Traffic Director instances all having similar functionality. The configuration mainly contains the description of:
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Servers to direct the incoming traffic (Origin Servers and Server Pools)
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IP address and port to listen for incoming requests (Listener)
The following steps must be performed when creating a configuration:
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A configuration must be created, with one HTTP virtual-server. This virtual server is configured to accept requests for www.oracle.com.
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A HTTP Listener must be created whose port is set as 80.
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Two origin-servers are created with the aforementioned host:port pairs.
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Then a server pool is created with these two servers, and the virtual server is associated with this server pool.
After the entities are created, this configuration is deployed on the hosts.
Using the Traffic Director Configuration Page
The performance metrics, performance information, or performance summary visible on the configuration home page, is at the configuration level that is, the performance is an aggregate of that entity's performance across the hosts on which the configuration instances are running. For example, the virtual server metrics visible on the configuration home page, are an aggregate of metrics at the instance level.
The Traffic Director Configuration page lists the following regions:
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Summary—Provides the general information regarding the configuration including how long the configuration has been up, its availability and the version of configuration. In addition, you can go directly to configure and monitor the Traffic Director by using the link to the Traffic Director Admin Console.
Also, the Monitoring and Diagnostics section lists whether there are any incidents involving the Traffic Director. An incident is an event that represents an issue requiring resolution. Click the incident to determine what needs attention.
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Response and Load
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Performance
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Instances
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Virtual Servers and Origin Servers
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Failover Group—Shows all the failover groups in the configuration. However, failover groups in the Instance Target home page shows only the failover groups of which the instance is a part.
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Exalogic—Shows information about Traffic Director Instances associated to the Exalogic Elastic Cloud target on which the region has been added.
For seeing detailed information about the Traffic Director Instances/Configurations shown in this region, click the links to navigate to the respective target home pages.
Note: You can view the Traffic Director Configuration details by selecting Configuration from the Target menu, then selecting Last Collected.
Adding Traffic Director Target Configuration
To manually add Traffic Director Configuration to Enterprise Manager, perform the following steps:
- From Enterprise Manager, select Add Target from the Setup menu located at the top-right of the page, then select Add Targets Manually.
- On the Add Targets Manually page, choose Add Targets Using Guided Process. In the Target Types menu, select Traffic Director.
- Click Add Using Guided Discovery.
Fill out the pages as described in:
Finding Configurations and Instances
Use the Find Configurations and Instances page to supply the Administration Server Properties:
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Administration Server Host
The name of the host where the Traffic Director Administration Server is running. Search for a host by clicking the Search icon located at the end of the field.
Note:
On selecting the host, the Agent URL field will be automatically populated.
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Administration Server SSL Port
SSL Port of the Administration Server.
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User Name
Name of the administrator allowed to access the Traffic Director Administration Server.
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Password
Password of the administrator allowed to access the Traffic Director Administration Server.
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SNMP Port
The port on which the SNMP agent is listening. All the SNMP agents on all Traffic Director instance hosts should be running on the same port.
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Oracle Home
Directory where the Traffic Director binaries have been installed.
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Agent URL
Enter the URL of the Management Agent running on the Administration Server host.
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Setup Prefix
Unique identifier for this setup. This ID will be prefixed to the names of the targets being discovered.
After you supply the information and click Continue, the Confirmation popup appears.
Click Close on the Confirmation popup, and then click Continue.
Possible Error Messages
These are the typical messages you see when the entered information is incorrect.
- Failed to find targets. Please check entered details OTD-70104 Unable to communicate with the administration server: Connection refused
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Cause: This typically means the host or port entered is incorrect.
Discovered Targets
The Add Traffic Director: Discovered Targets screen shows the discovered Traffic Director configurations and instances, along with the Management Agents that will be used for monitoring them.
Note: At this point, the targets have not yet been saved.
Click Add Targets to save them, or Back to go to the previous screen to review the details you entered.
The table on the page lists the Targets and Agent Assignments. The fields in the table are:
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Name—Name of the Traffic Director Configuration/Instance target.
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Type—Type of the target discovered. Discovered target types include Traffic Director Configuration and Traffic Director Instance.
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Agent URL—Management Agent that will be monitoring the target. All targets discovered are monitored by the Management Agent located on the Administration Server.
Viewing Results
The goal of the Add Traffic Director: Results page is to provide results. When you arrive at this page, the targets are already saved. Click OK to return to the Middleware page.
The Agent URL that you entered on the Find Configurations and Instances screen is used for monitoring all discovered targets. Once you assign the Management Agent, it cannot be changed.
For more information, see Oracle Enterprise Manager SNMP Support Reference Guide.
About Traffic Director Instance
After discovered, you can view the performance of entities like virtual-server, origin-servers, and instances, on the instance home page.
The performance visible in the instance home page (tables/charts showing metrics), is at the instance level and the metrics are calculated based on the data/traffic to/from that instance.
You access this page by clicking an instance in the Instance region of the Traffic Director Configuration page.
The performance metrics, performance information, or performance summary visible on the instance home page is at the instance level.
The Traffic Director Instance page lists the following regions:
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Summary—Provides the general information regarding the instance including how long the instance has been up, its availability and the version of the instance. In addition, you can go directly to configure and manage the Traffic Director instances by using the link to the Traffic Director Admin Console.
Also, the Monitoring and Diagnostics section lists whether there are any incidents involving the Traffic Director instances. An incident is an event that represents an issue requiring resolution. Click the incident to determine what needs attention.
The Summary region also includes statistics for the following: Instance, Resource Usage, and Proxy Cache.
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Response and Load
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CPU and Memory Usage
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Virtual Servers and Origin Servers
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Failover Groups—Shows only the failover groups to which the instance belongs.
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Exalogic—Shows information about Traffic Director Instances associated to the Exalogic Elastic Cloud target on which the region has been added. The Exalogic region is a region you can add using the Exalogic Elastic Cloud target home page.
For seeing detailed information about the Traffic Director Instances/Configurations shown in this region, click the links to navigate to the respective target home pages.
Note: You can view the Traffic Director Configuration details by selecting Configuration from the Target menu, then selecting Last Collected.
About Traffic Director Refresh Flow
After configurations are created, you can add new targets for newly added Configurations or Instances in the Traffic Director Administration Server, or delete the targets corresponding to Configurations or Instances that no longer exist in the Traffic Director Administration Server.
You can also modify target properties to reflect the addition or deletion of children. Only Configuration target properties are modified to reflect the addition or deletion of Instances.
You can access this flow by selecting Refresh Configuration from Traffic Director Configuration target menu.
Note: This flow adds and removes targets corresponding to all Traffic Director Administration Servers whose Configurations and Instances have been discovered under different setup prefixes.
Adding New Targets to Newly Added Configurations
To add new targets to newly added configurations, perform the following steps:
- From the Targets menu, select All Targets, then select a Traffic Director target.
- From the Traffic Director Configuration menu, select Refresh Configuration.
- Click Add Targets.
- On the resulting page, review that the newly added Configurations and their Instances are shown with refresh status New in the table. Click Save Updates to save the changes.
Now all new Configurations and their Instance targets are saved to the Repository and are being monitored.
Adding New Targets for Newly Added Instances of Configurations
To add new targets for newly added instances of configurations, perform the following steps:
- From the Targets menu, select All Targets, then select a Traffic Director target.
- From the Traffic Director Configuration menu, select Refresh Configuration.
- Click Add Targets.
- On the resulting page, review that the newly added Instances are shown as targets with refresh status New and their Configurations are shown with refresh status Modified in the table. Click Save Updates to save the changes.
Now all new Instance targets are saved to the Repository and are being monitored.
Deleting Targets of Configurations That Have Been Removed
To delete targets of configurations that have been removed, perform the following steps:
- From the Targets menu, select All Targets, then select a Traffic Director target.
- From the Traffic Director Configuration menu, select Refresh Configuration.
- Click Delete Targets.
- On the resulting page, review that the removed Configurations and their removed Instances are shown with refresh status Deleted in the table. Click Save Updates to save the changes.
Now all targets of removed Configurations and Instances have been removed from the Repository.
Deleting Targets of Instances That Have Been Removed
To delete targets of instances that have been removed, perform the following steps:
- From the Targets menu, select All Targets, then select a Traffic Director target.
- From the Traffic Director Configuration menu, select Refresh Configuration.
- Click Delete Targets.
- On the resulting page, review that the removed Instances are shown with refresh status Deleted in the table and their Configurations are shown with refresh status Modified. Click Save Updates to save the changes.
Now all targets corresponding to all removed Instances have been removed from the Repository.