8.1 Coexistence

This section provides information regarding the coexistence of the OES version of SMS with existing NetWare or Linux networks, and with previous versions of the product. The following topics are discussed:

8.1.1 Compatibility

SMDR

Wire Compatibility of the SMDR Protocol

The SMDR (see Section 1.2.1, Storage Management Data Requester) wire protocol is fully compatible between Linux and NetWare platforms. In other words, there are no changes in the wire protocol. This enables SMDR to communicate with other SMDRs on the same network irrespective of the platform that it is running on.

Discovery Protocols Used in SMDR

SMDR uses standard discovery and name resolution protocols. SMDR is enabled to SLP protocol version 1 upwards. SMDR also uses the hosts file to discover other SMDRs on the network and supports a policy ladder implementation to describe the order of priority of using any one mechanism over the other. All these methods are consistent and compatible on both NetWare and Linux.

SMDR on NetWare uses SAP as an additional discovery mechanism. SAP is not supported for SMDR on OES 11 SP2. See OES 11 SP2 on IPX-Based Networks for more information on how compatibility for SAP can be achieved.

Using iManager

You can use the latest SMS plug-in to iManager running on an OES 11 SP2 server to configure SMS services.

TSAFS

Data Stream Compatibility

TSAFS (see File System TSA (TSAFS)) uses the ECMA standard SIDF to format file system information into data streams. These streams are supplied to a backup application during backup. Backup applications usually present these streams during a restore, and the TSAFS interprets them.

TSAFS provides full data stream compatibility between NetWare and OES 11 SP2. In other words, TSAFS on Linux continues to maintain backward compatibility with all existing backups. That is, if the backup application provided TSAFS with a NetWare data stream from an older backup, it is capable of restoring this data correctly to NSS on OES 11 SP2 without any data loss. However, if an attempt is made to restore data from a NetWare file system or NSS file system, backing up to a non-NSS file system on OES would create data loss due to the inherent differences in file system semantics.

The following list indicates some of the metadata that is lost during a restore of NetWare traditional file system data or NSS file system data to non-NSS file systems on OES 11 SP2:

  • Secondary data streams

  • Extended attributes

  • Trustees

  • File owner/modifier/archiver information

  • Inherited rights filters

  • Directory quotas

  • User space restrictions

  • File attributes such as hidden, rename inhibit or copy inhibit

  • File characteristics such as compressed, migrated and sparse

8.1.2 Coexistence Issues

Backup Application Support for OES File System Backup

SMS services are consumed by various commercial backup applications. Backup applications might need to be upgraded to enable backing up of OES 11 SP2. For more information, refer to the commercial vendor’s backup application documentation.

SMS also supports a NetWare emulation mode (see NetWare Emulation Mode) where the Linux TSAFS exposes the system as though it were a native NetWare system. Some backup applications might use this option in the interim, while they move to a broader solution. Although the emulation mode itself might be deprecated in the future (After all backup applications have moved to backing up OES 2 or later natively), data backed up using this option would be recoverable by all future TSAs. nbackup (see Section 1.3, Backup Applications) supports backing up of OES 11 SP2. However, these backup applications are technology demonstrators and are not positioned as enterprise backup applications.

OES 11 SP2 on IPX-Based Networks

SMDR on NetWare can be configured to use Service Advertising Protocol (SAP) for locating other SMDRs in an IPX environment. SAP is not supported on OES 11 SP2, so in a pure IPX environment, SMDR on OES 11 SP2 cannot discover or resolve SMDRs on NetWare and vice versa. For SMS services on OES to work independently of platforms, discovery and name resolution protocols that are supported by SMDR must be common across all the platforms.

For more information on protocols supported by SMDR, see Section 3.4, Configuring SMDR.

Using SMS Across Mixed Node Clusters

Novell Cluster Services provides a migration path wherein a cluster can have a mix of NetWare and Linux nodes during a rolling cluster conversion. For more information regarding mixed node clusters, see the OES 11 SP2: Novell Cluster Services NetWare to Linux Conversion Guide.

TSAFS supports backing up of NSS file system resources on nodes in a mixed node cluster with failover/failback support. To back up cluster resources in a mixed node environment, use the TSAFS on OES 11 SP2 in the emulation mode of operation. See NetWare Emulation Mode for more information on how to use the emulation mode.