Configuring Cisco Access Registrar 5.0
This chapter describes how to configure a site. Cisco Access Registrar 5.0 is very flexible. You can choose to configure it in many different ways. In addition, you can write scripts that can be invoked at different points during the processing of incoming requests and/or outgoing responses.
Before you can take advantage of this flexibility, it helps to configure a simple site. This chapter describes that process. It specifically describes a site that has the following characteristics:
•Uses a single user list for all of its users
•Writes all of its accounting information to a file
•Does not use session management to allocate or track dynamic resources
This chapter contains the following sections:
•Configuring a Basic Site
To configure Cisco AR, use the aregcmd commands, which are command-line based configuration tools. These commands allow you to set any Cisco AR configuration option, as well as, start and stop the Cisco AR RADIUS server and check its statistics.
General Command Syntax
Cisco AR stores its configuration information in a hierarchy. Using the aregcmd command cd (change directory), you can move through this information in the same manner as you would through a hierarchical file system. Or you can supply full pathnames to these commands to affect another part of the hierarchy, and thus avoid explicitly using the cd command to change to that part of the tree.
The aregcmd commands are case insensitive, which means that you can use upper or lowercase letters to designate elements. In addition, when you reference existing elements in the configuration, you only need to specify enough of the element's name to distinguish it from the other elements at that level. For example, instead of entering cd Administrators, you can enter cd ad if no other element at the current level begins with ad.
You can use Cisco AR's command completion feature to see what commands are possible from your current directory location in the Cisco AR server hierarchy by pressing the Tab key. You can also press the Tab key after entering a command to see which objects you might want to manage.
The aregcmd commands are command-line order dependent; that is, the arguments are interpreted based on their position on the command line. To indicate an empty string as a place holder on the command line, use either two single quotes ('') or two double quotes (""). In addition, if you use any arguments that contain spaces, make sure to quote the arguments.
The aregcmd commands can be grouped into the following categories:
•Navigation commands—navigates within the Cisco AR hierarchy; commands include cd, ls, pwd, next, prev, filter, and find.
•Object commands—adds or deletes objects; commands include add and delete.
•Property commands—changes the value of properties; commands include set, unset, and insert.
•Server commands—manages the server; commands include save, validate, start, stop, reload, status, stats, and trace.
•Application commands—allows user access to the application; commands include login, logout, exit, quit, and help.
•Session management commands—queries the server about sessions, release active sessions, or count the number of sessions; commands include query-sessions, release-sessions, and count-sessions..
This chapter uses only a few of the above commands to configure the Cisco AR RADIUS server. For more information about all the aregcmd commands, see Chapter 2, Using the aregcmd Commands, in the Cisco Access Registrar User Guide.
Configuring a Basic Site
The simplest RADIUS server configuration is a site that uses a single user list for all its users, writes its accounting information to a file, and does not use session management to allocate dynamic resources.
To configure such a site, do the following:
1. Run the aregcmd command on your Cisco AR machine.
2. Configure the Cisco AR RADIUS server settings, such as the server name and the server defaults.
3. Add users by copying the sample users.
4. Configure the Network Access Server(NAS) clients and proxies that communicate with Cisco AR.
5. Change profile attributes as needed.
6. Save your changes and reload your Cisco AR RADIUS server.
aregcmd is the command-line interface program used to configure the Cisco AR server. The aregcmd program is located in $INSTALL/usrbin.
Step 1 Run the aregcmd command:
Step 2 When asked for "Cluster," press Enter.
Step 3 Enter your administrator name and password.
When you install Cisco AR software, the installation process creates a default administrator called admin with the password aicuser.
Changing the Administrator's Password
The administrator ID admin and password aicuser are default settings for all releases of Cisco AR software. For security purposes, you should change the password for admin at your earliest convenience. To change the administrator's password, complete the following steps:
Step 1 Use the cd command to change to the Administrators level. Cisco AR displays the contents of the Administrators object.
Step 2 Use the cd command to change to admin:
[ //localhost/Administrators ]
Entries 1 to 1 from 1 total entries
Step 3 Use the set command to change the administrator's password. You enter the password on the command line in readable form, however, Cisco AR displays it as encrypted.
The following example changes the password to
345. You are asked to reenter it for confirmation.
set Password 345
Optionally, use the set command to change the description of the admin administrator.
set Description local
Step 4 Use the ls command to display the changed admin.
Creating Additional Administrators
Use the add command to add additional administrators.
Step 1 Use the cd command to change to the Administrators level:
Step 2 Use the add command and specify the name of the administrator, an optional description, and a password.
The following example adds the administrator
testadmin, and password
add jane testadmin 123
Step 3 Use the ls command to display the properties of the new administrator:
Configuring the RADIUS Server
The top level of the Cisco AR RADIUS server is the Radius object itself. It specifies the name of the server and other parameters. In configuring this site, you only need to change a few of these properties.
DefaultAuthenticationService~ = local-users
DefaultAuthorizationService~ = local-users
DefaultAccountingService~ = local-file
DefaultSessionManager~ = session-mgr-1
Checking the System-Level Defaults
Because this site does not use incoming or outgoing scripts, you do not need to change the scripts' properties (IncomingScript and OutgoingScript).
Since the default authentication and authorization properties specify a single user list, you can leave these unchanged as well (DefaultAuthenticationService and DefaultAuthorizationService). And because you have decided to use a file for accounting information, you can leave this property unchanged (DefaultAccountingService).
Session management, however, is on by default (DefaultSessionManager). As you do not want to use session management, you must disable it. Use the set command, enter DefaultSessionManager, then specify an empty string by entering a set of double quotes:
set DefaultSessionManager ""
Note When you do not want Cisco AR to monitor resources for user sessions, you should disable session management because using it affects your RADIUS server performance.
You have now configured some of the properties for the RADIUS server. The next step is to add users.
Checking the Server's Health
To check the server's health, use the aregcmd command status. The following issues decrement the server's health:
•Rejection of an Access-Request
Note One of the parameters in the calculation of the Cisco AR server's health is the percentage of responses to Access-Accepts that are rejections. In a healthy environment, the rejection percentage will be fairly low. An extremely high percentage of rejections could be an indication of a Denial of Service attack.
•Running out of memory
•Errors reading from the network
•Dropping packets that cannot be read (because the server ran out of memory)
•Errors writing to the network.
Cisco AR logs all of these conditions. Sending a successful response to any packet increments the server's health.
Selecting Ports to Use
By default, Cisco AR uses well-known ports 1645 and 1646 for TCP/IP communications. Access Registrar can be configured to use other ports, if necessary. If you add additional ports, however, Access Registrar will use the added ports and no longer use ports 1645 and 1646. These ports can still be used by adding them to the list of ports to use.
To configure Cisco AR to use ports other than the default ports, complete the following steps:
Step 1 Change directory to /Radius/Advanced/Ports.
[ //localhost/Radius/Advanced/Ports ]
<no ports specified, will be using the well-known ports, 1645, 1646>
Step 2 Use the add command (twice) to add ports in pairs. (The ls is entered to show the results of the add command.)
[ //localhost/Radius/Advanced/Ports ]
Entries 1 to 2 from 2 total entries
Current filter: <all>
Note After modifying Access Registrar's default ports setting, to continue using ports 1645 and 1646, you must add them to the list of ports in /Radius/Advanced/Ports.
Step 3 Enter the save and reload commands to affect, validate, and save your modifications to the Cisco AR server configuration.
Reloading Server 'Radius'...
Server 'Radius' is Running, its health is 10 out of 10
Displaying the UserLists
The first subobject in the RADIUS hierarchy that you can configure is the Userlists. The UserLists object contains all of the individual UserLists, which in turn contain the specific users.
When Cisco AR receives an Access-Request, it directs it to an authentication and/or authorization Service. If the Service has its type set to local, the Service looks up the user's entry in the specific UserList, and authenticates and/or authorizes the user.
Cisco AR, by default, specifies a Service called local-users that has the type local and uses the Default UserList (Figure 4-1).
Figure 4-1 Choosing Appropriate Services
Displaying the Default UserList
Step 1 Use the cd command to change to UserLists/Default:
Step 2 Use the ls -R command to display the properties of the three users:
Cisco AR displays the three sample users:
bob who is configured as a PPP user
jane who is configured as a Telnet user
joe who is configured as either a PPP or Telnet user depending on how he logs in.
Adding Users to UserLists
Use the aregcmd command add to create a user under a UserList. The following lists the steps required to add a user:
Step 1 Use the add command to specify the name of a user and an optional description on one command line.
Step 2 Change directory to jane.
[ //localhost/Radius/UserLists/Default/jane ]
Name = jane
Password = <encrypted>
Enabled = TRUE
Group~ = Telnet-users
AllowNullPassword = FALSE
Step 3 Use the set command to provide a password for user jane.
set password jane
Set Password <encrypted>
Note When using the aregcmd command, you can use the add command and specify all of the properties, or you can use the add command to create the object, and then use the set command and property name to set the property. For an example of using the set command, see the "Adding a NAS" section.
To delete the sample users, or if you want to remove a user you have added, use the delete command.
From the appropriate UserList, use the delete command, and specify the name of the user you want to delete. For example, to delete user
beth from the Default UserList, enter:
The UserGroups object contains the specific UserGroups. Specific UserGroups allow you to maintain common authentication and authorization attributes in one location, and then have users reference them. By having a central location for attributes, you can make modifications in one place instead of having to make individual changes throughout your user community.
Cisco AR has three default UserGroups:
•Default—uses the script AuthorizeService to determine the type of service to provide the user.
•PPP-users—uses the BaseProfile default-PPP-users to specify the attributes of PPP service to provide the user. The BaseProfile default-PPP-users contains the attributes that are added to the response dictionary as part of the authorization. For more information about Profiles, see the "Configuring Profiles" section.
•Telnet-users—uses the BaseProfile default-Telnet-users to specify the attributes of Telnet service to provide the user. The BaseProfile default-Telnet-users contains the attributes that are added to the response dictionary as part of the authorization.
For this basic site, you do not need to change these UserGroups. You can, however, use the add or delete commands to add or delete groups.
The Clients object contains all NAS and proxies that communicate directly with Cisco AR. Each client must have an entry in the Clients list, because each NAS and proxy share a secret with the RADIUS server, which is used to encrypt passwords and to sign responses.
Note If you are just testing Cisco AR with the radclient command, the only client you need is localhost. The localhost client is available in the sample configuration. For more information about using the radclient command, see the "Using radclient" section.
Adding a NAS
You must configure your specific NAS from both ends of the connection. That is, you must configure Cisco AR for your NAS, and you must configure your NAS for Cisco AR.
Step 1 Use the cd command to change to the Clients level:
Step 2 Use the add command to add the NAS:
Step 3 Use the cd command to change directory to the QuickExampleNAS directory:
Step 4 Use the set command to specify the description
WestOffice, the IP address
220.127.116.11, the shared secret of
xyz, the Type as
set Description WestOffice
set IPAddress 18.104.22.168
set SharedSecret xyz
set Type NAS
set Vendor USR
set IncomingScript ParseServiceHints
The script, ParseServiceHints, checks the username for %PPP or %SLIP. It uses these tags to modify the request so it appears to the RADIUS server that the NAS requested that service.
Note When you are using a different NAS than the one in the example, or when you are adding NAS proprietary attributes, see the Cisco Access Registrar User Guide for more information about configuring Client and Vendor objects.
Configure your NAS, using your vendor's documentation. Make sure both your NAS and the Client specification have the same shared secret.
The Profiles object allows you to set specific RFC-defined attributes that Cisco AR returns in the Access-Accept response. You can use profiles to group attributes that belong together, such as attributes that are appropriate for a particular class of PPP or Telnet user. You can reference profiles by name from either the UserGroup or the user properties. The sample users, mentioned earlier in this chapter, reference the following Cisco AR profiles:
•default-PPP-users—specifies the appropriate attributes for PPP service
•default-SLIP-users—specifies the appropriate attributes for SLIP service
•default-Telnet-users—specifies the appropriate attributes for Telnet service.
Setting RADIUS Attributes
When you want to set an attribute to a profile, use the following command syntax:
set <attribute> <value>
This syntax assigns a new value to the named attribute. The following example sets the attribute Service-Type to Framed:
Step 1 Use the cd command to change to the appropriate profile and attribute.
Step 2 Use the set command to assign a value to the named attribute.
set Service-Type Framed
When you need to set an attribute to a value that includes a space, you must double-quote the value, as in the following:
set Framed-Routing "192.168.1.0/24 192.168.1.1"
Adding Multiple Cisco AV Pairs
When you want to add multiple values to the same attribute in a profile, use the following command syntax:
set <attribute> <value1> < value2> < value3>
The AV pairs cannot be added one at a time or each subsequent command will overwrite the previous value. For example, consider the following command entry:
set Cisco-AVpair "vpdn:12tp-tunnel-password=XYZ" "vpdn:tunnel-type=12tp" "vpdn:tunnel-id=telemar" "vpdn:ip-addresses=22.214.171.124"
Cisco-Avpair = vpdn:12tp-tunnel-password=XYZ
Cisco-Avpair = vpdn:tunnel-type=12tp
Cisco-Avpair = vpdn:tunnel-id=telemar
Cisco-Avpair = vpdn:ip-addresses=126.96.36.199
Note The example above is for explanation only; not all attributes and properties are listed.
Validating and Using Your Changes
After you have finished configuring your Cisco AR server, you must save your changes. Saving your changes causes Cisco AR to validate your changes and, if there were no errors, commit them to the configuration database.
Using the save command, however, does not automatically update your server. To update your server you must use the reload command. The reload command stops your server if it is running, and then restarts the server, which causes Cisco AR to reread the configuration database.
You must save and reload your configuration changes in order for them to take effect in the Cisco AR server.
Saving and Reloading
From anywhere in the radius object hierarchy, enter the save and reload commands.
Step 1 Use the save command to save your changes:
Step 2 Use the reload command to reload your server.
Testing Your Configuration
Now that you have configured some users and a NAS, you are ready to test your configuration. There are two ways you can test your site:
1. You can act as a user and dial in to your NAS, and check that you can successfully log in.
2. You can run the radclient command, and specify one of the default users when making a request.
You can use the radclient command simple to create and send a packet. The following example creates an Access-Request packet for user
john with password
john, and the packet identifier
p001. It displays the packet before sending it. It uses the send command to send the packet, which displays the response packet object identifier,
p002. Then, the example shows how to display the contents of the response packet.
Step 1 Run the radclient command.
. /radclient -s
Step 2 The radclient command prompts you for the administrator's username and password (as defined in the Cisco AR configuration). Use admin for the admin name, and aicuser for the password.
Cisco Access Registrar 5.0 RADIUS Test Client
Copyright (C) 1995-2008 by Cisco Systems, Inc. All rights reserved.
Logging in to localhost... done.
Step 3 Create a simple Access-Request packet for User-Name john and User-Password
john. At the prompt, enter:
simple john john
The radclient command displays the ID of the packet
Step 4 Enter the packet identifier:
Packet: code = Access-Request, id = 0, length = 0, attributes =
NAS-Identifier = localhost
Step 5 Send the request to the default host (localhost), enter:
Step 6 Enter the response identifier to display the contents of the Access-Accept packet:
Packet: code = Access-Accept, id = 1,\
length = 38, attributes =
Login-IP-Host = 188.8.131.52
Login-Service = Telnet
Login-TCP-Port = 541
Troubleshooting Your Configuration
If you are unable to receive an Access-Accept packet from the Cisco AR server, you can use the aregcmd command trace to troubleshoot your problem.
The trace command allows you to set the trace level on your server, which governs how much information the server logs about the contents of each packet. You can set the trace levels from zero to four. The system default is zero, which means that no information is logged.
Setting the Trace Level
Step 1 Run the aregcmd command.
Step 2 Use the trace command to set the trace level to 1-5.
Step 3 Try dialing in again.
Step 4 Use the UNIX tail command to view the end of the name_radius_1_trace log.
host% tail -f /opt/CSCOar/logs/name_radius_1_trace
Step 5 Read through the log to see where the request failed.
To configure Cisco AR to perform accounting, you must do the following:
1. Create a service
2. Set the service's type to file
3. Set the DefaultAccountingService field in /Radius to the name of the service you created
After you save and reload the Cisco AR server configuration, the Cisco AR server writes accounting messages to the accounting.log file in the /opt/CSCOar/logs directory. The Cisco AR server stores information in the accounting.log file until a rollover event occurs. A rollover event is caused by the accounting.log file exceeding a pre-set size, a period of time transpiring, or on a scheduled date.
When the rollover event occurs, the data in accounting.log is stored in a file named by the prefix accounting, a date stamp (yyyymmdd), and the number of rollovers for that day. For example, accounting-20081107-14 would be the 14th rollover on November 07, 2008.
The following shows the properties for a service called CiscoAccounting:
[ //localhost/Radius/Services/local-file ]
OutagePolicy~ = RejectAll
FilenamePrefix = accounting
MaxFileSize = "10 Megabytes"
Before you can perform SNMP configuration, you must first stop the SNMP master agent, then configure your local snmpd.conf file. The snmpd.conf file is the configuration file which defines how the Cisco AR server's SNMP agent operates. The snmpd.conf file might contain any of the directives found in the DIRECTIVES section.
Enabling SNMP in the Cisco Access Registrar Server
To enable SNMP on the Cisco AR server, launch aregcmd and set the /Radius/Advanced/SNMP/Enabled property to TRUE.
[ //localhost/Radius/Advanced/SNMP ]
InputQueueHighThreshold = 90
InputQueueLowThreshold = 60
MasterAgentEnabled = TRUE
set Enabled TRUE
Stopping the Master Agent
You stop the Cisco AR SNMP master agent by stopping the Cisco AR server.
Modifying the snmpd.conf File
The path to the snmpd.conf file is /cisco-ar/ucd-snmp/share/snmp. Use vi (or another text editor) to edit the snmpd.conf file.
There are three parts of this file to modify:
•System Contact Information
Access control defines who can query the system. By default, the agent responds to the public community for read-only access, if run without any configuration file in place.
The following example from the default snmpd.conf file shows how to configure the agent so that you can change the community names, and give yourself write access as well.
Complete the following steps to modify the snmpd.conf file.
Step 1 Look for the following lines in the snmpd.conf file for the location in the file to make modifications:
Step 2 First map the community name (COMMUNITY) into a security name that is relevant to your site, depending on where the request is coming from:
# sec.name source community
com2sec local localhost private
com2sec mynetwork 10.1.9.0/24 public
The names are tokens that you define arbitrarily.
Step 3 Map the security names into group names:
group MyRWGroup v2c local
group MyRWGroup usm local
group MyROGroup v1 mynetwork
group MyROGroup v2c mynetwork
group MyROGroup usm mynetwork
Step 4 Create a view to enable the groups to have rights:
Step 5 Finally, you grant the two groups access to the one view with different write permissions:
# context sec.model sec.level match read write notif
access MyROGroup "" any noauth exact all none none
access MyRWGroup "" any noauth exact all all none
The following example shows the default configuration that sets up trap recipients for SNMP versions v1 and v2c.
Note Most sites use a single NMS, not two as shown below.
trapsink zubat trapcom 162
trap2sink ponyta trapcom 162
Note trapsink is used in SNMP version 1; trap2sink is used in SNMP version 2.
trapcommunity defines the default community string to be used when sending traps. This command must appear prior to trapsink or trap2sink which use this community string.
trapsink and trap2sink are defined as follows:
trapsink hostname community port
trap2sink hostname community port
System Contact Information
System contact information is provided in two variables through the snmpd.conf file, syslocation and syscontact.
Look for the following lines in the snmpd.conf file:
# System contact information
syslocation Your Location, A Building, 8th Floor
syscontact A. Person <firstname.lastname@example.org>
Restarting the Master Agent
You restart the Cisco AR SNMP master agent by restarting the Cisco AR server.
Configuring Dynamic DNS
Cisco AR supports the the Dynamic DNS protocol providing the ability to update DNS servers. The dynamic DNS updates contain the hostname/IP Address mapping for sessions managed by Cisco AR.
You enable dynamic DNS updates by creating and configuring new Resource Managers and new RemoteServers, both of type dynamic-dns. The dynamic-dns Resource Managers specify which zones to use for the forward and reverse zones and which Remote Servers to use for those zones. The dynamic-dns Remote Servers specify how to access the DNS Servers.
Before you configure Cisco AR you need to gather information about your DNS environment. For a given Resource Manager you must decide which forward zone you will be updating for sessions the resource manager will manage. Given that forward zone, you must determine the IP address of the primary DNS server for that zone. If the dynamic DNS updates will be protected with TSIG keys, you must find out the name and the base64 encoded value of the secret for the TSIG key. If the resource manager should also update the reverse zone (ip address to host mapping) for sessions, you will also need to determine the same information about the primary DNS server for the reverse zone (IP address and TSIG key).
If using TSIG keys, use aregcmd to create and configure the keys. You should set the key in the Remote Server or the Resource Manager, but not both. Set the key on the Remote Server if you want to use the same key for all of the zones accessed through that Remote Server. Otherwise, set the key on the Resource Manager. That key will be used only for the zone specified in the Resource Manager.
Note For proper function of AR 5.0 GUI, the DNS name resolution for the server's hostname should be defined precisely.
To configure Dynamic DNS, complete the following steps:
Step 1 Launch aregcmd.
Step 2 Create the dynamic-dns TSIG Keys:
This example named the TSIG Key, foo.com, which is related to the name of the example DNS server we use. You should choose a name for TSIG keys that reflects the DDNS client-server pair (for example, foo.bar if the client is foo and the server is bar), but you should use the name of the TSIG Key as defined in the DNS server.
Step 3 Configure the TSIG Key:
set Secret <base64-encoded string>
The Secret should be set to the same base64-encoded string as defined in the DNS server. If there is a second TSIG Key for the primary server of the reverse zone, follow these steps to add it, too.
Step 4 Use aregcmd to create and configure one or more dynamic-dns Remote Servers.
Step 5 Create the dynamic-dns remote server for the forward zone:
This example named the remote server ddns which is the related to the remote server type. You can use any valid name for your remote server.
Step 6 Configure the dynamic-dns remote server:
set Protocol dynamic-dns
set IPAddress 10.10.10.1 (ip address of primary dns server for zone)
set ForwardZoneTSIGKey foo.com
set ReverseZoneTSIGKey foo.com
If the reverse zone will be updated and if the primary server for the reverse zone is different than the primary server for the forward zone, you will need to add another Remote Server. Follow the previous two steps to do so. Note that the IP Address and the TSIG Key will be different.
You can now use aregcmd to create and configure a resource manager of type dynamic-dns.
Step 7 Create the dynamic-dns resource manager:
This example named the service ddns which is the related to the resource manager type but you can use any valid name for your resource manager.
Step 8 Configure the dynamic-dns resource manager.
set Type dynamic-dns
set ForwardZone foo.com
set ForwardZoneServer DDNS
Finally, reference the new resource manager from a session manager. Assuming that the example configuration was installed, the following step will accomplish this. If you have a different session manager defined you can add it there if that is appropriate.
Step 9 Reference the resource manager from a session manager:
set 5 DDNS
Note The Property AllowAccountingStartToCreateSession must be set to TRUE for dynamic DNS to work.
Step 10 Save the changes you have made.
Testing Dynamic DNS with radclient
After the Resource Manager has been defined it must be referenced from the appropriate Session Manager. You can use radclient to confirm that dynamic DNS has been properly configured and is operational.
To test Dynamic DNS using radclient, follow these steps:
Step 1 Launch aregcmd and log in to the Cisco AR server.
Step 2 Use the trace command to set the trace to level 4.
Step 3 Launch radclient.
Step 4 Create an Accounting-Start packet.
acct_request Start username
set p [ acct_request Start bob ]
Step 5 Add a Framed-IP-Address attribute to the Accounting-Start packet.
Step 6 Send the Accounting-Start packet.
Step 7 Check the aregcmd trace log and the DNS server to verify that the host entry was updated in both the forward and reverse zones.