If this is your first time using ACS, it is important to take the time to learn how to navigate the interface. Note that the main web page of ACS is divided into frames. You access different menu items on the left-hand side of the page, perform configuration in the middle, and have access to some help on the right-hand side. Because you use the menu a great deal in you configurations, the next sections look at each menu item and what types of configuration can be performed at each level. User SetupWhen you select the User Setup menu item, your middle frame changes to the "select" screen. Here, you can do a few things. You can add a new user, search for an existing user, find users alphabetically or numerically, or simply list all users at one time. User Setup is seen in Figure 6-1. Figure 6-1. User SetupTo begin your configuration, add a username. To do so, follow these steps:
NOTE By selecting the List All Users button after creating your user, you should see a single user entry on the right-hand side of the ACS interface. This ensures that the entry has been successfully created. Group SetupTo begin your configuration, recap what you have configured thus far. You have a user called aaauser who has a password of cisco and is placed in the default group. This user is authenticated to the Cisco Secure database only. To examine the group that this user is in, follow these steps:
You can note a few highlights while you are here. First of all, take a look at jump to at the top of the screen. This feature is a real time saver. Try it out a few times by jumping to the IP address assignment section and then back to access restrictions. Notice that in the group configuration you have the ability to configure time-of-day access restrictions. This is not available at the user level. You can also configure Callback, IP Assignment, and TACACS+ settings. Under TACACS+ Settings you can configure shell command authorizations, apply privilege levels, set auto-commands, and so on. These types of configurations are discussed in Chapter 8, "Configuring User Groups," and Chapter 10, "Configuring Shared Profile Components." NOTE Some of the fields might not be visible in either the Group Setup or User Setup. As you become more familiar with ACS, you will be able to enable or disable certain fields at either the group level or the user level. This capability is explained in detail in Chapter 7 and Chapter 8, so do not worry if some of the items discussed in this chapter are not visible in you ACS device. When you make group changes, you are required to submit and restart the ACS services. Your changes do not take place until you have done so. If you are making multiple changes to a group, it is best to submit without restart after each change until you have completed all changes, and then restart the ACS services. Shared Profile ComponentsShared Profile Components allows you to specify Shell Command Authorization Sets and PIX Shell Command Authorization Sets. By creating these command authorization sets, you can control the commands a user can execute on a device by applying the command authorization set to the user profile in the TACACS+ settings, or at the group level. Figure 6-5 displays the Shared Profiles Components configuration menu. By default, you can select Shell Command Authorization Sets and PIX Shell Command Authorization Sets. Optionally, you can configure Downloadable ACLs or Management Center Authorization Sets. For these options to be visible, you must select them in the Interface Configuration page. Figure 6-5. Shared Profile ComponentsAnother benefit to the Shared Profile Components configuration page is the ability to configure Shared Network Access Restrictions. By selecting one of these links, for example, Shell Command Authorization Sets, you are taken to the configuration page for this shared profile component. This configuration is discussed in Chapter 10. You can see what this configuration page looks like in Figure 6-6. As you can tell, at this point, none are defined. Figure 6-6. Shell Command Authorization SetsNetwork ConfigurationThe Network Configuration section is where you add, delete, or modify settings for AAA clients. At least one entry in this section should be placed there during install of ACS. You can see this in Figure 6-7. The AAA client is the device you added during the install. The AAA server is the Windows server, or rather the ACS server itself, that is entered here during the server installation. Figure 6-7. Network ConfigurationBy selecting that entry, note that you can control the IP address of the device, key, and authentication method. You can also see a total of four check boxes in Figure 6-8. They are as follows:
Figure 6-8. AAA Client Setup for ACSWhen you make changes to an AAA client, you must submit and restart the ACS services, similar to group changes. If you want to delete an AAA client, you are also required to submit and restart the service for changes to take effect. System ConfigurationUnder System Configuration, you find many sub-configuration links beginning with Service Control. These sub-configuration links can be seen in Figure 6-9. This is where you can stop and start the ACS services. You can also do so in the Service Control of Windows 2000. By stopping the ACS service inside of ACS, you do not stop the ACS web server. If you want to stop the ACS web server, you need to do so in the Service Control of Windows. This web service is called CSAdmin. Figure 6-9. System ConfigurationThe next System Configuration feature that you can manipulate is Logging. In this feature is where you can configure the local logging configuration, such as failed attempts and TACACS+ and RADIUS Accounting. You also configure Open DataBase Connectivity (ODBC) and remote logging here, as well as other ACSs. Date Format control is straightforward. This is where you can change the format of the date displayed on reports. After you change the format, you must log out of the server to actually see the changes take place. You can log out of ACS, short of closing the browser, in a few ways. One way is by clicking the Cisco Systems logo in the top left corner of the web browser screen and then selecting the Log off button. Another method is by clicking on the X in the top right portion of the window. The next option is Local Password Management. From here you can set password length, as well as password options. You can also configure options for Remote Password Change and logging of password changes. As for ACS Backup, you can schedule backups to be done manually or at specific times. You can specify a location for the backup files to be stored as well as manage the files. When ACS is backed up, it creates a file with the extension of .dmp. This file is now present when you enter the ACS Restore link. Here you have the ability to select from numerous backup files, as well as determine if you want to restore the Users and Groups, System Configuration, or both. ACS Service Management enables the administrator to determine how often to test the availability of ACS authentication services. This is the CSMon service configuration. This allows ACS to test itself and take action when its test is unsuccessful. The available actions, should no authentications be recorded, are as follows:
If the reboot option is selected, this causes the server that is running ACS to reboot. You also have the ability to add custom actions to this list. You can also decide that you want to log attempts to log in to disabled accounts. Do this by selecting the check box labeled Generate event when an attempt is made to log in to a disabled account. This is also where you can configure e-mail notifications and NT Event Log setup. The ACS Certificate Setup is where you configure the ACS device with digital certificates. You use this when you configure the ACS to use https for administrative sessions. Global Authentication Setup is where you can allow protocols such as PEAP, EAP-TLS, EAP-MD5, and MS-CHAP. Interface ConfigurationMoving on to the Interface Configuration menu item, as seen in Figure 6-10, you find a selection from the following sub-configuration links, depending on whether you have selected TACACS+ or a form of RADIUS when you entered your AAA client:
Figure 6-10. Interface ConfigurationNOTE If you do not see RADIUS options here, you need to add an AAA client that uses the RADIUS protocol. Interface Configuration is directly affected by Network Configuration. The User Data Configuration link enables you to customize the fields that appear in the user setup and configuration. Here you can add fields such as phone number, work location, supervisor name, or any other pertinent information. The TACACS+ (Cisco IOS) link enables the administrator to configure TACACS+ settings as well as add new TACACS+ services. You can also configure advanced options that affect what you see in your interface. It is important you understand how this works. Depending on the current configuration of your server, if you go to the TACACS+ link, you might or might not see two columns. If you do see two columns, you are able to configure user-level settings as well as group level. Figure 6-11 displays what you see before enabling per-user TACACS+/RADIUS attributes. Figure 6-11. TACACS+ (Cisco IOS) Before User AttributesIn Figure 6-12, you can see the change to the TACACS+ (Cisco IOS) settings page after going through the following steps:
Figure 6-12. TACACS+ (Cisco IOS) After User AttributesYou should now have two columns available, User and Group. By selecting these options at the user level or group level, you enable these configuration options within each menu. Here is where the user-to-group relationship comes into play. If an option is selected to appear in both the user and group configurations, and the user-level configuration is different than the group level, the user-level configuration takes precedence. Most of the features are available in both user and group configurations with a few exceptions. At the user level, you can configure passwords, expiration, and static IP addresses. At the group level, you can configure password aging as well as time-of-day restrictions for different categories. Administration ControlThe Administration Control section is where you configure all aspects of ACS for administrative access. Here you have the ability to add administrators and configure Access Policy. Information such as IP addresses that are allowed to access ACS, IP addresses that are not allowed to access ACS, and HTTP port allocation can be configured here. Recall that ACS uses port 2002 as the listening port, but after connection to that port is made, you are redirected to a random port number. When ACS is positioned behind a firewall, this random port assignment becomes a security issue. You have the ability to specify a range of ports used so that you can configure access restrictions within your firewall to match, as seen in Figure 6-13. This is especially helpful when using a PIX Firewall. Figure 6-13. HTTP Port AllocationNOTE The Secure Socket Layer Setup option was not available in version 3.0. Session Policy enables you to alter the timeout, allow automatic local logins, and respond to invalid IP addresses. You can also choose to lock administrator access after a certain number of tries. NOTE Audit Policy enables you to configure File Management and Directory Management options. External User DatabaseIn this section, you see where to configure an unknown user policy. This same topic is covered in extensive detail in Chapter 11, "System Configuration." You also configure database group mappings to external user databases as well as perform the actual database configuration. Further, you are given a list of compatible databases, and you can choose which one you will configure to be used with ACS. The servers that are available for use as an external database are as follows:
Each version of ACS includes more and more support for external databases while greatly improving the functionality of the ACS database. Reports and ActivityThe Reports and Activity section provides a wealth of tools in not only troubleshooting, but also monitoring your network. In the time that I have been a security instructor, I make it a point to teach students that if you are going to log it, you better look at it. So many times I have been in networks running Intrusion Detection Systems, SYSLOG, and other types of monitoring, yet nobody takes the time to look through the logs. Within ACS, you have the ability as an administrator to monitor your network security on a number of levels. The available logs that ACS keeps for you follow:
The Reports and Activity interface is seen in Figure 6-14. Figure 6-14. Reports and ActivityAs far as viewing these reports goes, you can view them in the ACS interface or from the hard drive of the ACS server. The logs are stored as CSV files. You can view the reports in spreadsheet programs like Microsoft Excel. For even more functionality, you can import these into third-party software such as Crystal Reports. These reports are discussed in more detail in Chapter 12. If you do not have access to the hard drive of the ACS server, you are given the ability to download the logs from the ACS interface. Online DocumentationThe online documentation of ACS is there to help you out if you get stuck. If you have followed along on an ACS server up to this point, you have probably noticed that in different configuration menus you find some brief help on the right-hand side of your screen in the browser window. The online help is more detailed configuration information. You can access the PDF form if you have the CD-ROM, or it is available in the ZIP file that you downloaded from the Cisco website. |