Cisco SCMS Subscriber Manager LEGs User Guide, Release 3.7.x
DHCP Forwarder Application
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DHCP Forwarder Application

Table Of Contents

DHCP Forwarder Application

Introduction

Installing the DHCP Forwarder

Uninstalling the DHCP Forwarder

DHCP Forwarder Veritas Cluster Server Agent

Adding a DHCP Forwarder Resource

Removing a DHCP Forwarder Resource


DHCP Forwarder Application


Revised: March 22, 2012, OL-24194-06

Introduction

This chapter describes how to install the DHCP forwarder application as well as adding and removing resources.


Note This module is only relevant when the DHCP Lease Query Login Event Generator (LEG) is installed on the subscriber manager server.


The DHCP Forwarder application acts as a bridge between the DHCP Lease Query LEG and the DHCP servers. The LEG sends a request to the DHCP Forwarder, which then forwards the request to the appropriate DHCP server. The DHCP Forwarder passes the replies from the DHCP servers to the LEG. The LEG signals the forwarder which server should receive each request. Therefore, no special configuration is needed for this application.

Because only root privileged applications can open ports under 1024 (DHCP uses ports 67 and 68), the DHCP Forwarder runs with root privileges.

Installing the DHCP Forwarder

Uninstalling the DHCP Forwarder

DHCP Forwarder Veritas Cluster Server Agent

Installing the DHCP Forwarder


Step 1 Run the DHCP Forwarder installation script from the SM DIST root directory.

You must run the DHCP Forwarder installation script as root.

#./install-forwarder.sh
 
   

The installation script extracts the DHCP Forwarder distribution to the sm-inst-dir \sm\server\addons\dhcp-forwarder directory (sm-inst-dir refers to the SM installation directory). The script adds the initialization scripts to their location according to the machine's OS.

Step 2 Run the DHCP Forwarder application.

The DHCP Forwarder application can be run using one of the following methods:

Restart the machine. The initialization script will start the application automatically.

Run the following command as root:

#/etc/init.d/p3dhcpforwarder start
 
   

Note It is not possible to run the install-forwarder.sh script if the /etc/motd file exists. The file should be moved or removed prior to running the script. The ps -eaf | grep DHCP command can be used to view the running process of the DHCP Forwarder.



Uninstalling the DHCP Forwarder


Step 1 Stop the DHCP Forwarder application.

Run the following command as root to stop the application.

#/etc/init.d/p3dhcpforwarder stop
 
   

Step 2 Remove the DHCP Forwarder application startup and shutdown scripts.

Run the following command as root to remove the startup and shutdown scripts.

For Solaris:

# rm /etc/rc*.d/[SK]*p3dhcpforwarder 
# rm /etc/init.d/p3dhcpforwarder
 
   

For Red Hat:

# rm /etc/rc.d/rc*.d/[SK]*p3dhcpforwarder 
# rm /etc/rc.d/init.d/p3dhcpforwarder
 
   

Step 3 Remove the DHCP Forwarder application directory.

Run the following command to remove the application.

# rm -r ~pcube/sm/server/addons/dhcp-forwarder
 
   

DHCP Forwarder Veritas Cluster Server Agent

To verify that the DHCP Forwarder process is active at all times, a Veritas Cluster Server (VCS) Agent of type OnOnlyProcess is added as a resource.

Adding a DHCP Forwarder Resource

Removing a DHCP Forwarder Resource

Adding a DHCP Forwarder Resource


Step 1 Import the OnOnlyProcess agent's type from the /opt/VRTSvcs/bin/OnOnlyProcess/OnOnlyProcess.cf file.

Step 2 Add an OnOnlyProcess resource called DHCP_Forwarder to the service group.

Step 3 Note the path and arguments of the DHCP Forwarder.

Run the following command via a Telnet session on each of the servers:

>ps -ea -o pid,s,args
 
   

Look for the line containing the text "DHCP_FORWARDER". This line contains the path and arguments of the DHCP Forwarder to be used in the next step.

Step 4 Define the OnlineCmd, PathName, and Arguments parameters.

Define the parameters as follows:

OnlineCmd—Type the DHCP Forwarder start command:

/etc/init.d/p3dhcpforwarder start
 
   

PathName—Type the DHCP Forwarder process path (from the previous step). For example: /opt/pcube/j2re1.4.2_05/bin/java

Arguments—Type the DHCP Forwarder process arguments (from the previous step). For example: DAPP=DHCP_FORWARDER -jar /opt/pcube/sm/server.

For further information about the parameters, see Figure 10-1.

Figure 10-1 Adding a DHCP Forwarder Resource


Note The arguments line might seem shorter than the actual full argument list. This is perfectly acceptable.



Removing a DHCP Forwarder Resource


Step 1 Right-click on the DHCP Forwarder Resource icon and choose Delete from the drop-down menu (Figure 10-2).

Figure 10-2 Removing a DHCP Forwarder Resource