Converting a Server Component to a Load Balancer Component

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Riverbed Technology, Inc. 199 Fremont Street San Francisco, CA 94105 Phone 415.247.8800 Fax 415.247.8801 www.riverbed.com/cascade

Tech Note #067

Product: xx60 Profiler Version: 9.5 Date: 1/11/13

Converting a Server Component to a

Load Balancer Component

Cascade®_{Profiler service definitions include service components, each of which represents one or more}

devices involved in delivering the service. In versions before 9.0, the Profiler did not directly track end-to-end connections in a service that included a load balancer or application delivery controller (ADC) in its delivery path. There were several ways to deal with this limitation. These included approaches such as setting up a single server component to represent both the virtual addresses and SNAT address of the load balancer, and setting up two server components, one to represent the load balancer’s virtual addresses and another to represent its SNAT addresses.

If you used one of these approaches to represent a load balancer in a service definition, you can update your service definitions to convert the server components to load balancer components. Versions 9.0 and higher support full end-to-end tracking of service delivery paths that include load balancers. The conversion procedure depends on what component or components currently represent the load balancers in the service. This document describes conversion procedures for cases in which the load balancer is currently represented by:

• Case 1: Single VIP/SNAT component and a load-balanced server pool component – One component that represents both the virtual IP addresses and the SNAT addresses.

• Case 2: Separate VIP and SNAT components and a load-balanced server pool component – One component that represents the virtual IP addresses and a second component that represents the SNAT addresses.

• Case 3: Separate VIP and Proxy End Users components and a load-balanced server pool

component – One component that represents the virtual IP addresses and a second component

that represents a proxy for the end user addresses. (SNAT is not used in this case.) • Case 4: Separate VIP and a load-balanced server pool component – One component that

represents the virtual IP addresses and a second component that represents a load-balanced server pool. (SNAT is not used in this case.)

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• Case 5: Physical servers – No components are representing any parts of a load balancer. The service has a component representing physical servers, and you are introducing a load balancer into the service for the first time.

Case 1: Single VIP/SNAT component and a load-balanced server

pool component

In this service definition, one component represents both the virtual IP addresses and the SNAT addresses. In the example below, the component labeled “Web” represents both the VIP and SNAT addresses. The component labeled “WebFarm” represents the load-balanced server pool.

If you have defined a single component and simply grouped the VIP and SNAT addresses together, you can convert that component into a load balancer component by editing its definition, as follows:

1. Open the Services menu to see a list of all existing services. Choose the name of the service to be edited. This opens an Edit Service window for the service.

2. In the Service Map section, right click the component that you want to convert to a load

balancer and choose View/Edit from the right-click menu. (“Web” in this example.) This displays an Edit Component window. Ensure that the correct component is displayed in this window. 3. Click Edit to expand the Edit Component window.

4. Change the Type setting to Load Balancer VIPs.

Note: If the definition of the server component you are converting to a load balancer

component includes an “Outside Hosts/Subnets” specification, this will be lost during the conversion procedure. Load balancer service component definitions do not include an “Outside Hosts/Subnets” specification for excluding hosts from the definition.

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Changing the Type setting to Load Balancer VIPs opens a text box for specifying the IP addresses of the virtual servers (VIPs) running on the load balancer. The box will currently include both VIP addresses and SNAT addresses. In this example, the VIP address is 10.100.120.100 and the SNAT address is 10.100.120.108.

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5. Select the load balancer. If you have defined the load balancer on the Configuration >

Integration > Load Balancers page, then you can select it from the drop-down list. This example uses a load balancer named “DataCenterF5.”

If you have not yet defined the load balancer, click New to get a window in which you can define it. All that is necessary for this procedure is for the load balancer to have a name. You can specify the other information as a separate task.

6. Select the type of connections the load balancer uses for the downstream servers. In this example SNAT is used for all connections.

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7. Cut the SNAT addresses out of the VIPs box and paste them into the SNAT Addresses box. Ensure that the VIPs box contains only VIP addresses.

8. If convenient, edit the VIPs box to provide the protocol and port for each VIP address. This is not necessary for completing this conversion procedure, and you can do it at a later time. This step is optional if the load balancer cannot be queried to validate or update the configuration.

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9. Click Save to apply the new component definition to the service definition. Check the Service Map to ensure that the load balancer is correctly represented.

At this point in the procedure, the conversion is complete, but not yet applied to the service. You can go to Step 4 on the Edit Service page and edit the service monitoring configuration or leave the page and convert other server components to load balancer components.

10. When you are ready to apply the new service definition, select Step 5 on the page and then click

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Case 2: Separate VIP and SNAT components and a

load-balanced server pool component

In this service definition, you have preserved separate components for the VIP and SNAT addresses. One component represents the virtual IP addresses and a second component represents the SNAT addresses.

The conversion involves recording the addresses represented by each of the two components that are currently representing the load balancer (Web and WebLB in the example in the figure above), merging the two components, and then redefining the merged component as a load balancer component. You need to know the VIP addresses and SNAT addresses to redefine the merged component.

Step 1: Record the addresses

The VIP and SNAT addresses should be recorded because you will need to separate them when the two components are merged. Also, the merging process may combine contiguous addresses into a CIDR block, which you may need to replace with individual addresses.

To record the addresses,

2. In the Service Map section, right click the component that represents the VIP addresses. (This is the Web component in the example in the figure above.) Choose View/Edit from the right-click menu. This displays an Edit Component window.

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4. Record the VIP addresses and then click Cancel to close the window.

5. In the Service Map section, right click the component that represents the SNAT addresses. (This is the WebLB component in the example.) Choose View/Edit from the right-click menu to display the Edit Component window.

6. Click Edit to expand the Edit Component window.

7. Record the SNAT addresses and then click Cancel to close the window.

Step 2: Merge the two components

To merge the components,

1. Ensure that Step 3 on the Edit Service page is selected so that the “Step 3: Review Service Definition” section of the page is displayed.

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2. Select the Components tab.

3. On the Components tab, select the two components to be merged. These are Web and WebLB in this example.

4. Click Merge.

5. In the Merge Components window, choose the component whose name you want to retain. In this example, “Web” will be the name of the merged component.

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6. Click Save and check that there is now one component containing all the addresses.

Step 3: Redefine the merged component

The configuration is now the same as the configuration described in “Case 1: Single VIP/SNAT

component and a load-balanced server pool component” above. Continue with the procedure described in that section to complete the conversion.

Case 3: Separate VIP and Proxy End Users components and a

load-balanced server pool component

This service definition does not use SNAT for the components between the end users and the servers. Instead, one component represents the virtual IP addresses and a second component represents a proxy for the end user addresses. In the example below, the “Web” component represents the VIP addresses of the load balancer.

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To convert these components into a load balancer component, merge the two components and then redefine the merged component as a load balancer.

Step 1: Merge the two components

To merge the components,

2. In the Service Map section, right click the component that represents the VIP addresses of the load balancer. (“Web” in this example.)

3. Choose View/Edit from the right-click menu. This displays an Edit Component window. 4. Click Edit to expand the Edit Component window.

5. Copy the addresses (for later pasting) and click Cancel to close the Edit Component window. 6. In the Service Map section, right click the component that serves as a proxy for the end users.

(This is the ProxyEndUsersLB component in the example in the figure above.) Choose View/Edit from the right-click menu. This displays an Edit Component window.

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8. Delete the addresses that are currently in the ProxyEndUsersLB component and paste in the addresses that you copied from the Web component.

9. When the end user proxy component has the same addresses as the component representing the VIP addresses (“Web” in this example), click Save.

10. Ensure that Step 3 on the Edit Service page is selected so that the “Step 3: Review Service Definition” section of the page is displayed.

11. Select the Components tab.

12. On the Components tab, select the two components to be merged. These are Web and ProxyEndUsersLB in this example.

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13. Click Merge.

14. In the Merge Components window, select the component whose name you want to retain. In this example, “Web” will be the name of the merged component.

15. Click Save and check that there is now one component containing all the addresses.

Step 2: Redefine the merged component

To redefine the merged component as a load balancer,

1. In the Service Map section, right click the merged component and choose View/Edit from the right-click menu. This displays an Edit Component window.

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3. In the Type field, select Load Balancer VIPs.

4. In the Load Balancer field, select the load balancer. If you have defined the load balancer on the Configuration > Integration > Load Balancers page, then you can select it from the drop-down list. If you have not yet defined the load balancer, click New to get a window in which you can define it. All that is necessary for this procedure is for the load balancer to have a name. You can specify the other information as a separate task.

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5. Select the type of connections the load balancer uses for the downstream servers. (In this example, SNAT was not used.)

6. If convenient, edit the VIPs box to provide the protocol and port for each VIP address. This is not necessary for completing this conversion procedure, and you can do it at a later time.

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At this point in the procedure, the conversion is complete, but not yet applied to the service. You can go to Step 4 on the Edit Service page and edit the service monitoring configuration or leave the page and convert other server components to load balancer components.

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Case 4: Separate VIP and a load-balanced server pool

component

In this service definition, one component represents the virtual IP addresses and a second component represents a load-balanced server pool. The segments between the EndUsers and Web represent traffic between the users and the load balancer VIPs. The segment between the EndUsers and the WebFarm represents traffic between the load balancer and the load-balanced server pool.

The conversion requires redefining a segment and then redefining a component, as follows.

1. In the Service Map section, right click the segment that connects the end users component to the load-balanced server poolcomponent. In the example in the figure above, this segment is named Web-BackEnd.

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3. In the Clients section, change the client to be the component that represents the VIP addresses. (“Web” in this example.)

4. Click Save. Note that the Service Map displays the new relationship.

5. In the Service Map section, right click the component that represents the VIP addresses of the load balancer. (“Web” in this example.)

6. Choose View/Edit from the right-click menu. This displays an Edit Component window. 7. Click Edit to expand the Edit Component window.

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8. In the Type field, select Load Balancer VIPs.

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10. Select the type of connections the load balancer uses for the downstream servers. (In this example, SNAT was not used.)

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11. If convenient, edit the VIPs box to provide the protocol and port for each VIP address. This is not necessary for completing this conversion procedure, and you can do it at a later time.

At this point in the procedure, the conversion is complete, but not yet applied to the service. You can go to Step 4 on the Edit Services page and edit the service monitoring configuration or leave the page and convert other server components to load balancer components.

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Commit Changes.

Case 5: Physical servers

In this service definition, a component represents physical servers, and you are introducing a load balancer into the service for the first time. The service component must be converted from representing physical servers to representing a load balancer.

The component named “Web” in this example represents the load-balanced server pooland should be renamed appropriately. Then a new component must be created to represent the load balancer. Finally, segments must be defined to reflect the application delivery path.

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Step 1: Rename the webserver component

To rename the web server component,

2. In the Service Map section, right click the component that the web servers (“Web” in this example) and choose View/Edit from the right-click menu. This displays an Edit Component window. Ensure that the correct component is displayed in this window.

3. Click Edit to expand the Edit Component window.

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Step 2: Create the load balancer component

1. On the upper right side of the Edit Service page, click New Component.

2. Enter the name for the load balancer in the Create New Component window. For example, “Web.”

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4. Enter the load balancer VIP addresses. If convenient, also provide the protocol and port for each VIP address. This is not necessary for completing this conversion procedure, and you can do it at a later time.

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6. Specify the type of connections to the servers.

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8. Click Save and observe that the new load balancer component now appears on the Service Map.

Step 3: Reconfigure the service segments

To connect the new load balancer component into the service,

1. On the Service Map, right-click the segment connecting the EndUsers and WebServerFarm components and choose View/Edit from the right click menu. This opens the Edit Segment window.

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2. In the Server section of the window, change the segment to connect to the Web component (the load balancer).

3. Click Save and observe that the Service Map now shows the EndUsers component connecting to the load balancer.

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4. On the upper right of the Edit Service page, click New Segment.

5. In the Create New Segment window, specify the following: • Segment Name: Web-LB

• Clients: Choose the load balancer component Web

• Ports/Apps: tcp/80; In this example, this is used by connections between the load balancer and the load-balanced server pool. Your protocol, port or application may be different. • Servers: Choose the WebServerFarm component

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6. Click Save and observe that the Service Map now displays the load balancer between the EndUsers and WebServerFarm components.

At this point in the procedure, the conversion is complete, but not yet applied to the service. You can go to Step 4 on the Edit Services page and edit the service monitoring configuration or leave the page and convert other server components to load balancer components.

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For additional information

If you have questions or need additional information, please contact Riverbed Support at: Phone – United States and Canada: 1 888 782 3822

Phone – outside U.S. and Canada: +1 415 247 7381 Email: [email protected]