What is a SMDR why is it needed?

(Last modified: 21Oct2002)

This document (10060218) is provided subject to the disclaimer at the end of this document.

goal

fix

The Storage Management Data Requester (SMDR) is the communication module in the SMS architecture. It provides transparent access to SMS services in an intranet by exposing a set of SMS APIs which can be used to access local or remote SMS services. These APIs are used by backup applications such as Backup Exec.

In order to understand what a SMDR configuration is and why it is required, it would be beneficial to understand the features of SMDR and how it works.

Features of SMDR
The features of the SMDR 5.04 include:
Protocol Independence:SMDR 5.04 is protocol independent and does not depend on Sequenced Packet Exchange (SPX) or Internetwork Packet Exchange (IPX) protocols. For NetWare 5.1, the requester uses TCP/IP for communicating with other SMDRs. Although SMDR 5.04 can be configured to support TCP/IP, SPX/IPX, or TCP/IP and SPX/IPX, both protocols are supported by default. SMDR versions prior to 5.00 use the SPX protocol.The protocols can be specified in the configuration file, SMDR.CFG. (See below Using the SMDR Configuration File for more information)
NDS for Name Resolution: Prior to version 5.00, SMDR used only Service Advertising Protocol (SAP) for locating other SMDRs on the network. Each SMDR advertised the server name where it was loaded using service type 0x23F. But in an IP environment, NDS and Service Location Protocol (SLP) replaces SAP.
NDS Registration and Name Resolution: SMDR 5.04 creates an SMS Remote Procedure Call (RPC) object in NDS. The default tree of the server (the tree in which the server is present) is used for NDS registration.
The SMS RPC object is defined with the following attributes:

·      Common Name - Name of the server in which the SMDR is located
·      Status - Indicates whether the SMDR is active or inactive
·      Protocol - List of protocols for which the SMDR has listeners
·      Version - Version number of the SMDR
·      Services - List of services registered with the SMDR

The SMDR creates an instance of this RPC class at the SMDR Context location in the server's default tree. The SMDR Context is specified in the SMDR.CFG file which can be edited at any time.
Multiple SMDRs are grouped together to reduce the search scope in NDS. A SMDR Group object defines this search scope. This group represents an instance of a predefined group class in the NDS schema. Any number of such groups can exist in NDS. The SMDR can become a member of one or more groups by registering its object's (SMS RPC object) context.
When SMDR requires name resolution, it searches all members of the SMDR Group at SMDR Group Context. The SMDR Group Context and SMDR Group are specified in the configuration file, SMDR.CFG. The SMDR queries SAP if the configuration file has changed. Though SAP is enabled by default, it can be disabled.
Name Resolution Using SLP:SMDR 5.04 can also be configured to use Service Location Protocol (SLP) for locating other SMDRs. This enables SMDRs to locate other SMDRs running on servers that belong to different trees. Every SLP enabled SMDR will register itself in the SMDR.Novell domain when loaded. The SLP enabled SMDRs will query this domain for locating registered SMDRs.

Backward Compatibility of SMDR 5.04
The SMDR included with NetWare 4.11 uses Service Advertising Protocol (SAP) for advertising and name resolution in an Sequenced Packet Exchange (SPX) environment. Use this SMDR on 4.x servers. For NetWare 5.1, the requester uses TCP/IP for communicating with other SMDRs. Though both the SMDR's have the same NLM name (SMDR.NLM), PSMDR (SMDR 5.04) and SMDR are used to distinguish between the new and old SMDR respectively. SMDR 5.04 will work on 4.x servers if NDS is installed and SLP is disabled.
With Backup Exec for NetWare on a NetWare 4.11 server with SMDR 5.04, and a restore of files backed up on a NetWare 5.1 server is attempted, the restore s.tops if the files are open and will not complete the restore. Close all the files before the backup and restore utility is run. In some cases, the backup will not complete and the application will have to be unloaded.

Conclusion
The SMDR configuration is used to establish the protocols supported by SMDR, the SMDR Context, SMDR Group Context and SMDR Group, whether to disable SAP, NDS and/or Service Location Protocol (SLP).
Note that SMDR 5.04 will work on 4.x servers if NDS is installed and SLP is disabled.
For more information go to:
http://www.novell.com/documentation/lg/nw51/docui/index.html#../back_enu/data/hhc3nq5m.html

document

Document Title:	What is a SMDR why is it needed?
Document ID:	10060218
Solution ID:	NOVL38743
Creation Date:	01Feb2001
Modified Date:	21Oct2002
Novell Product Class:	Groupware NetWare Novell eDirectory

disclaimer

The Origin of this information may be internal or external to Novell. Novell makes all reasonable efforts to verify this information. However, the information provided in this document is for your information only. Novell makes no explicit or implied claims to the validity of this information.
Any trademarks referenced in this document are the property of their respective owners. Consult your product manuals for complete trademark information.