Posted: 8 Sep 2005

Peter J. Strifas
Premium Support Engineer
NYC-Metro/Northeast

Many Novell customers are evaluating Open Enterprise Server (OES) for their next OS upgrade. For some, OES has one very compelling feature, the ability to run Novell services atop of a Linux kernel. And when we say that, we're specifically talking about SUSE LINUX Enterprise Server 9.

For most Novell customers, setting up and maintaining infrastructure services for their network environment is a common practice. Aside from the obvious DNS and DHCP, there's Network Time Protocol (NTP) and Service Location Protocol (SLP). NTP provides time to your environment while SLP provides a method of finding services reliably without having to maintain client-side configuration files or server-side configuration files.

SLP or Service Location Protocol is a process by which nodes on a network can discover and select services and/or resources. By nature, this process is dynamic and requires little or no static configuration as previously required.

This document walks you through configuring your SLP environment to use OpenSLP on Novell's OES based on SUSE LINUX Enterprise Server (SLES) as a Directory Agent (DA). Additional information on configuring a Novell Client on a Windows workstation to use SLP services from the same OES-SLES server is included.

Key Components/Configurations

1. SLPD and SLP.CONF
2. Verifying SLP functionality on the server
3. Novell Client Configuration on Windows
4. Verifying SLP on the workstation

The SLP Daemon and SLP.CONF file

On OES-SLES, the component that provides SLP services is SLPD (/etc/init.d/slpd) or better known as the SLP Daemon. This process has a configuration file called SLP.CONF (/etc/slp.conf).

The best way to understand the configuration of SLP on OES-SLES is to review an SLP.CONF file.

Sample contents of an SLP.CONF file (located at /etc/slp.conf)

	net.slp.DAAddresses = 192.168.1.115
	net.slp.useScopes = GLOBAL
	net.slp.isBroadcastOnly = false
	net.slp.isDA = true
	net.slp.interfaces = 192.168.1.115

Breaking down the SLP.CONF

The first line (net.slp.DAAddresses = 192.168.1.115) specifies the IP Address of an SLP DA. If there are multiple DA's, separate with a comma as such:

net.slp.DAAddresses = 192.168.1.115, 192.168.1.111

The second line (net.slp.useScopes = GLOBAL) specifies the name of an SLP SCOPE. With SLP v2, you must specify scope names. The value GLOBAL is user-determined.

The third line (net.slp.isBroadcastOnly = false) sets the broadcast capabilities of the SLP DA.

The fourth line (net.slp.isDA = true) sets this server to act as an SLP DA. The default value is false.

The last line in the configuration (net.slp.interfaces = 192.168.1.115) defines which interface to 'bind' the SLP DA to. If none is specified, the SLP DA will function across all network interfaces so this setting is optional.

Once you have edited the SLP.CONF file correctly, you'll need to restart the SLP Daemon using the following command:

/etc/init.d/slpd restart or
/etc/init.d/slpd stop
/etc/init.d/slpd start

[Note: On OES-SLES, you can use rcslpd restart or rcslpd stop and rcslpd start as commands]

Once the configuration is complete, you can use the SLPTOOL on the server to check SLP information.

Useful SLPTOOL commands

slptool findsrvs service
- finds SLPDAs configured in your environment (via the SLPD.CONF file)
(see graphic above)

slptool findsrvs service:ndap.novell
- finds Partition information stored with this server's SLP

example:

service:ndap.novell:///bos.novell.uoc.OESLAB.,0
service:ndap.novell:///novell.uoc.OESLAB.,0
service:ndap.novell:///provo.uoc.OESLAB.,0
service:ndap.novell:///OESLAB.,0

[Note: type 'slptool' at the console prompt to view more information].

Additional Information on DA servers

If your environment requires additional OpenSLP DA servers, you can copy the SLP.CONF file to additional servers and restart the SLP Daemon on each designated server. This will add that functionality to that server.

Remember to edit the SLP.CONF file on all servers to include all DA IP Addresses.

And lastly, OpenSLP DA servers different from traditional NetWare DA servers in that they do not add information to eDirectory. OpenSLP DA servers maintain the SLP information in memory only and do not forward the information to eDirectory.

Client side configuration

The Novell Client configuration settings needed for SLP are located in the Service Location Tab of the Novell Client Properties.

Click the Service Location tab:

The Scope List setup is accomplished by typing the name of the SLP SCOPE into the Scope List text field, then click ADD. Check off the checkbox for STATIC so the client will not discover SLP Scopes via other methods (multicast/broadcast/DHCP unless your environment requires it to do so).

Next, setup the Directory Agent List by typing the IP Address or DNS name of the server configured as the Directory Agent. Again, check STATIC as well. If you have several servers acting as Directory Agents, list them within this field.

At this point, you'll be asked to reboot the workstation to complete the Novell Client Service Location setup, click No.

[Note: Service Location can also be setup automatically during the Novell Client installation via ACU or UNATTENDED installation process not covered in this document.]

Completing the Novell Client setup requires editing the Windows Registry with the following Windows Registry setting:

[HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesSRVLOCParameters]

"Use SingleEquals in Where (V2)"=dword:00000001

For more details, refer to TID: http://support.novell.com/cgi-bin/search/searchtid.cgi?/10095884.htm

This setting is important. Without this setting, the SLP configuration will not function properly.

Verifying the Novell Client Configuration

To verify that your SLP configuration is functioning properly on the Windows Workstation after a login, start a DOS prompt --> Start >> Run --> type CMD >> Hit Enter.

At the command prompt, type 'slpinfo /a >> slpinfo.txt'. This creates a text file called slpinfo.txt with SLP information the workstation's SRVLOC.SYS component has. What you'll want to review in this file is:

Total Packets OUT
          [if this is empty or zero, it points to a problem with the client configuration]
- Scope List matches your SLP environment
          [if this is wrong, check the client configuration]
- DA IP Address section has your DAs listed, Active and servicing the proper scopes
- Local Interface section ? Last Addr In
          entry should be one of your DAs.
          If it's a broadcast address, then the workstation isn't finding a DA and is getting multicast traffic responses.

This last item would point to either a mis-configuration in the Directory Agent listing on the workstation (or that it's checked Static in a DHCP environment) or if this is a DNS entry, verify the DNS information.

Additional Troubleshooting

The best troubleshooting tool is LAN Traces of 'problems'. The optimal SLP process during log on takes 6-8 packets (depending on your partitioning and context levels). Anything more than that would point to an inefficiency only. Any error message during log on (tree or server not found) would point to failure as well.