6

Extended Content Verification (ECV)

• Working with the ECV Service Monitor

Working with the ECV Service Monitor

When you set up an extended content verification (ECV) service monitor for a wide IP, you can monitor not only the availability of a port or service on a server, but also the availability of a specific file on a particular server. An ECV service monitor verifies whether a specific file is available using the HTTP, HTTPS, or FTP network services. You can also specify a search string for the ECV monitor. When you specify a search string, the 3-DNS not only verifies that a file is available, but also that whatever you specify in the search string is in the file.

An ECV service monitor can help you ensure that clients are getting what they are after, and that they will not get an error, whether they are looking for information, making an online purchase, or uploading software.

An ECV service monitor works in the following manner: if the file responds appropriately to the ECV query, the server where the file resides is marked as up and the client connection request is sent to that server. If the file does not respond as expected to the ECV query, the server where the file resides is marked as down, and the client will not be sent to that server.

Defining ECV service monitors

You can define ECV service monitors using the Configuration utility, or from the command line. You define ECV monitors for wide IPs only.

To define ECV service monitors using the Configuration utility

1. In the navigation pane, click Wide IPs.
   The Wide IP List screen opens.
   
   
2. In the Wide IP column, click the wide IP to which you want to add an ECV service monitor.
   The Modify Wide IP screen opens.
   
   
3. Add the settings for the ECV near the bottom of the screen, and click Update. For more information on the ECV settings, click Help on the toolbar.
   
   

To define ECV service monitors from the command line

1. At the command prompt, type 3dnsmaint to open the 3-DNS Maintenance menu.
   
   
2. On the 3-DNS Maintenance menu, choose Edit 3-DNS Configuration to open the wideip.conf file.
   
   
3. Use the syntax shown in Figure 6.1 to define an ECV service monitor.
   
   You should place all ECV service monitor statements just before the wide IP pool definitions in the wideip.conf file.
   
   

Note: You can set up ECV monitors that use the https protocol only on crypto 3-DNS systems.

Figure 6.1 Syntax for defining ECV service monitors

 ecv {     
      protocol        <http | https | ftp>     
      filename        <"path and file name">    
      scan_level      <all | first>    
      user          [ <"user name"> ]    
      hashed_password [ <"hashed version of server password"> ]    
      search_string "<search string text>"    
   }  

Figure 6.2 shows a sample ECV statement that defines an ECV service monitor in the wideip.conf file.

Figure 6.2 Sample ECV service monitor definition

 ecv {     
      protocol        http     
      filename        "/home/user/readme.txt"    
      scan_level      all    
      user            "jones"    
      hashed_password "22AECCCD9CA9C2CC8B"    
      search_string   "Configuration Notes"    
   }     

Using the search string option

With the search string option, you can specify text or characters that you want the ECV monitor to verify within the file. The search string functionality is based on POSIX regular expression matching. Regular expressions are a matching tool for text and characters within a file. When you include a search string in an ECV service monitor, the 3-DNS not only verifies that the file exists, but also that whatever text you type for the search string is available, exactly as you typed it, within the file. The most basic search string options are simply text. For a more advanced search string, you can use the POSIX regular expression characters shown in Table 6.1 .

Note: For more information on working with POSIX regular expressions, refer to the re_format man page. To view the re_format man page, type the following at the command line:

man re_format