14

Configuring a Content Converter

• Introducing the content converter
• Configuring the content converter
• Additional configuration options

Introducing the content converter

The content converter feature performs conversion of URLs to ARLs (Akamai Resource Locators). ARLs point to copies of URL targets that are stored on geographically nearby servers on the Akamai Freeflow NetworkTM for greater speed of access. The conversion from URL to ARL is performed whenever a client accesses a web page on a customer site containing a URL with an ARL counterpart, giving it the name on-the-fly content conversion. On-the-fly content conversion has the advantage that the HTML source does not need to be updated each time a new ARL is added.

Note: The content converter feature is usable only by customers of the Akamai Freeflow Network. In addition, the features required to configure this option are available only on the BIG-IP HA and Enterprise versions.

Figure 14.1 Content converter configured on a BIG-IP system

The content converter is set up as a proxy for the customer web site server. Figure 14.1 shows a basic content converter configuration. The proxy passes resource requests from a client to the server without modifying the content. The HTML resource sent in reply, however, is intercepted by the proxy and URLs converted to ARLs where applicable according to rules defined in a configuration file. The client then receives an HTML page with the ARL substituted for the URL and retrieves the resource from the Akamai Freeflow Network server.

Configuring the content converter

Setting up content conversion on the BIG-IP includes the following steps:

• Configure the on-the-fly conversion software.
• Create a pool of web servers handling HTTP connections.
• Create a virtual server that handles connections for the web servers.
• Create the content converter gateway.

  You must perform the tasks in this order. If the software is not configured first, the attempt to create a proxy will fail. The following section explains the essential tasks, and shows how you would perform each task in order to implement the example configuration.

Configuring the on-the-fly conversion software

The first task is to configure the Akamai configuration file for the on-the-fly conversion software.

1. On the BIG-IP, bring up the Akamai configuration file /etc/akamai/config1.conf in an editor like vi or pico.
2. Under the heading [CpCode] you will find the text default=XXXXX. Replace the Xs with the CP code provided by your Akamai Integration Consultant. (When contacting your consultant, specify that you are using the BIG-IP on-the-fly Akamaizer based on Akamai's 1.0 source code.) Example:
   
   

   default=773

3. Under the heading [Serial Number] you will find the text staticSerialNumber=XXXXX. Replace the Xs with the static serial number provided by your Akamai Integration Consultant. Example:
   
   

   staticSerialNumber=1025

   Note: You need to set this value only if algorithm under [Serial Number] is set to static, as it is in the default file. If you choose to set algorithm to deterministicHash or deterministicHashBounded, the static serial number is not applicable. If you are unsure which method to select, contact your Akamai Integration Consultant.

4. Under the heading [URLMetaData] you will find the text httpGetDomains=XXXXX. Replace the Xs with an FQDN for a node containing content to be served. Create additional httpGetDomains entries for additional FQDN. Example:
   
   

   httpGetDomains=image.f5.com
   httpGetDomains=support.f5.com

5. Save and exit the file.
6. For each FQDN specified in an httpGetDomains entry, create an entry in the /etc/hosts file mapping the FQDN to the IP address of a server containing the actual content. If the content is referenced by a virtual server on the same BIG-IP as the content converter proxy, do not use the virtual server address. Instead, use the address of an individual member node. Note that these mappings in etc/host do not have to correspond to the mappings of the FQDNs as seen by the outside world. Example:
   
   

   10.3.0.11 image.f5.com
   192.168.200.30 support.f5.com

Creating the load balancing pool

Next, you need to create a load balancing pool.

To create a pool using the Configuration utility

1. In the navigation pane, click Pools.
   The Pools screen opens.
2. Click the Add button.
   The Add Pool screen opens.
3. For each pool, type the pool name and member addresses in the Add Pool screen. (For additional information about configuring a pool, click the Help button.)
   
   

   Configuration notes

   For this example, create an HTTP pool named http_pool. This pool contains the following members:
   10.3.0.11
   10.3.0.12

To define a pool from the command line

To define a pool from the command line, use the following syntax:

b pool <pool_name> { member <member_definition> ... member <member_definition> }

For example, if you want to create the pool http_pool, you would type the following command:

b pool http_pool { \

member 10.3.0.11:80 \

member 10.3.0.12:80 }

Creating the virtual server

After you create the load balancing pool, you can create a virtual server that references the pool load balancing the web servers. You can create the virtual server using the Configuration utility or from the command line.

To define a standard virtual server that references a pool using the Configuration utility

1. In the navigation pane, click Virtual Servers.
2. Click the Add button.
   The Add Virtual Server screen opens.
3. Type the virtual server address and pool name. For additional information about configuring a virtual server, click the Help button.
   
   

   Configuration note

   To create the virtual server described in Figure 14.1, create a virtual server 192.168.200.20 on port 80 that references the pool content server pool http_pool.

To define a standard virtual server mapping from the command line

Use the bigpipe virtual command as shown below. Also, note that you can use host names in place of IP addresses, and that you can use standard service names in place of port numbers.

b virtual <virt_ip:port> use pool <pool_name>

To create the virtual server for the configuration in Figure 14.1, on page 14-1, you would type:

b virtual 192.168.200.20:80 use pool http_pool

Creating a content converter gateway using the Configuration utility

After you create the virtual server, you can create a content converter gateway.

To create a content converter gateway using the Configuration utility

1. In the navigation pane, click Proxies.
   The Proxies screen opens.
2. Click the Add button.
   The Add Proxy screen opens.
3. In the Add Proxy screen, configure the attributes you want to use with the proxy. For additional information about configuring a Proxy, click the Help button.
   
   

   Configuration notes

   To create the configuration shown in Figure 14.1, on page 14-1:

   Use 192.168.200.10 for the proxy address and 192.168.200.20 for the destination address.

   Select port 80 or http for both the proxy and destination ports.

   Select Local Virtual Server as the destination target.

   Enable the proxy for akamaization.

Creating a content converter gateway from the command line

Use the following command syntax to create a proxy:

b proxy <ip>:<port> { target server <ip>:<port> akamaize enable }

For the example in Figure 14.1, you would type:

b proxy 192.168.200.10:80 { \

target virtual 192.168.200.20:80 \

akamaize enable }

Additional configuration options

Whenever you configure a BIG-IP, a number of options are available to you:

• You have the option in all configurations to configure a BIG-IP redundant system for fail-over. Refer to Chapter 6, Configuring a Redundant System, in the BIG-IP Reference Guide.
• All configurations have health monitoring options. Refer to Health Monitors in Chapter 4, Configuring the High-Level Network, in the BIG-IP Reference Guide.
• When you create a pool, there is an option to set up persistence and a choice of load balancing methods. Refer to Pools in the Chapter 4, Configuring the High-Level Network, in the BIG-IP Reference Guide.