DIGITAL OpenVMS Disk Services for Windows NT

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1 DIGITAL OpenVMS Disk Services for Windows NT Introduction Windows NT is growing as a corporate standard, because Microsoft continues enhancing the operating system, and developers continue to add applications and programming tools. However, expanding Windows NT beyond the desktop into the enterprise is moving ahead slowly, due to the limitation of enterprise-class functionality. According to a recent survey of Windows NT implementers, their primary concerns about deploying mission-critical business applications on Windows NT include: - Reliability - Failover capabilities - Security - Performance - Scalability - Support As mission-critical applications are being deployed and its data stored on Windows NT platforms, the questions persist: Is this business-critical data being maintained? Is it being backed-up? Are its storage devices reliable? What system managers want are enterpriselevel system management and high availability Windows NT products. They also want the benefits of centralized storage for their Windows NT data. And they want all this now! Many of the most successful early implementers of Windows NT at the enterprise level are also OpenVMS users. They rely on the scalability, reliability, and high availability of OpenVMS systems and want the same advantages for Windows NT. Reliable Storage Solution DIGITAL OpenVMS Disk Services for Windows NT allows users to store Windows NT data on OpenVMS to take advantage of the reliability of 24X365 computing and the economies of centralized storage. OpenVMS Alpha nodes in a cluster, or standalone systems, serve virtual disks to Windows NT systems. The virtual disk functions like a locally attached disk, although its data is actually stored on a disk on the OpenVMS system. The virtual disk is formatted with a native Windows NT file system, such as NTFS or FAT, using standard Windows NT tools. The Windows NT system can share the virtual disk out to user workstations or desktops via the standard Windows NT network sharing mechanisms. 1

2 Storage on the OpenVMS Cluster OpenVMS Disk Services for Windows NT Windows NT Server User Workstations Windows 3.1 Windows 95 Windows NT Nodes in the OpenVMS Cluster at tier 1 serve virtual disks to Windows NT servers at tier 2. The Windows NT servers use standard network sharing mechanisms to share the disks among Windows 95 and Windows NT desktops at tier 3. The Windows NT computer at tier 2 uses TCP/IP to communicate with the OpenVMS Cluster at tier 1. The key capabilities provided by DIGITAL OpenVMS Disk Services for Windows NT include: Physically Centralized storage Automatic failover of disk services in the OpenVMS cluster Flexibility in allocating storage to Windows NT systems Investment protection Compatibility with Windows NT applications Scalability DIGITAL OpenVMS Disk Services for Windows NT is an extension to DIGITAL's current Windows NT storage alternatives. It is for customers who want to store Windows NT data on OpenVMS, but who do not need to share files between the two operating systems. OpenVMS applications cannot access the data stored on the virtual disk. Customers who need to share data between OpenVMS and Windows NT applications must use either PATHWORKS, or other file-sharing solutions. 2

3 How is it Different from PATHWORKS? PATHWORKS and OpenVMS Disk Services for Windows NT provide Windows NT computers with very different types of services: PATHWORKS provides file and print services. The file services let you share data between OpenVMS and Windows NT applications. Both OpenVMS and Windows NT applications can access the same files. OpenVMS Disk Services for Windows NT provides disk services. It serves raw disk blocks, not files, to connected Windows NT computers. All file system operations take place on the Windows NT computer. OpenVMS applications cannot access the data stored on the virtual disk, just as they cannot access the data stored on a real disk that is locally attached to the Windows NT computer. In many cases, OpenVMS Disk Services for Windows NT will provide performance improvements when compared with file-sharing solutions. This is because operational path is more direct and there is no need for data translation or file system operations on the OpenVMS server. 3

4 Virtual Disks for Centralized Storage DIGITAL OpenVMS Disk Services for Windows NT enables the OpenVMS system to serve virtual disks to Windows NT computers. The virtual disk behaves exactly like a locally attached disk, although its data is actually stored in a container file on the OpenVMS system. The following picture shows a Windows NT computer whose D: and E: drives represent virtual disks whose data is stored in the OpenVMS container files USER.NTDS and REPORT.NTDS respectively SERVER Windows NT Local System Disk (C:) User (D:) Report (E:) Service User Service Report REPORT.NTDS USER.NTDS OpenVMS Windows NT data can be stored centrally on OpenVMS, and existing OpenVMS backup schedules can be used to back up both your Windows NT and OpenVMS data. OpenVMS Disk Services for Windows NT is a flexible method for allocating storage. Users can divide large OpenVMS disks into smaller virtual disks and connect each virtual disk to a different Windows NT computer. For example, OpenVMS has a 40 GB RAID array that can be used to provide storage for three Windows NT application servers. The user creates three virtual disks: a 20 GB disk for the Microsoft Exchange mail server, and two 10 GB disks, one for the Lotus Notes server and one for the web server. 4

5 Service Failover Storing Windows NT data on OpenVMS disks allows users to take advantage of the enhanced data availability provided by the failover capabilities found in OpenVMS clusters. OpenVMS Disk Services for Windows NT provides failover support for critical Windows NT data. The nodes in the OpenVMS Cluster are configured as either active or standby. In the second illustration, the standby connection becomes active after damage to active node in the OpenVMS Cluster. Standby nodes in the OpenVMS Cluster provide automatic failover of disk services. The failover is transparent to Windows NT users accessing the virtual disk; they continue accessing the disk, unaware that a different node in the OpenVMS Cluster is serving it. OpenVMS Disk Services has a client component on Windows NT, and a server component on OpenVMS, and uses TCP/IP to communicate between them. Multiple network paths can be configured between the client and server components. If one path fails, another path is made available for accessing the virtual disk. This is achieved by setting up one or more standbys for each disk service provided by the OpenVMS Cluster. High Availability Operation The OpenVMS Cluster provides safe, reliable storage for the virtual disk's data. Standby nodes are established for each disk service that the OpenVMS Cluster provides, so if the node currently providing the service fails, the service automatically fails over to another node in the OpenVMS Cluster. The failover is transparent to users. 5

6 For example: An organization s server is destroyed by fire. The server s virtual disk is safe because it is being served by an OpenVMS Cluster that is distributed across various sites and survives the fire. To get the service up and running again, the organization simply uses OpenVMS Disk Services' pointand-click interface to connect another server to the virtual disk. Only one Windows NT computer can connect to a particular disk service at any one time. If the computer currently connected to the service fails, you can connect a different Windows NT computer to the service. Creating A Virtual Disk The management and control of OpenVMS Disk Services for Windows NT are culturally compatible with familiar commands and command-lines on the OpenVMS Server side and graphical user interface on the Windows NT Client side. A device driver on the Windows NT system makes a virtual disk look like a locally attached disk. From the Windows NT system, the virtual disks are formatted with a native file system, such as NTFS or FAT. Because the disk service is hosted on an OpenVMS Cluster, it will move between nodes in the event of an unplanned shutdown. Windows NT clients automatically reconnect when the link is re-established. DCL commands set up and manage disk services on the OpenVMS system, and a pointand-click interface on the Windows NT system makes it easy to connect and disconnect virtual disks as needed. Here is an example of how simple it is to create a virtual disk with OpenVMS Disk Services. Creating the OpenVMS Container File for the Disk Service, is the first step in setting up a virtual disk service for a Windows NT client. Log on to an OpenVMS Alpha node and use the NTDS CREATE CONTAINER command. $NTDS CREATE CONTAINER DISK$MEDIA:[NTDS]NEWS.NTDS/SIZE= The /SIZE qualifier specifies how large the virtual disk should be, in blocks. The NTDS CREATE CONTAINER command creates a container file of the specified size. 6

7 Configuring the OpenVMS Cluster to Provide the Disk Service, is the second step to provide virtual disk service. On the OpenVMS selected to provide service, and then on each node identified to be standby for the service: 1. Log on to the OpenVMS Alpha node and set process privileges. Give your process the SYSNAM and SYSPRV privileges: $ SET PROCESS /PRIVILEGE=(SYSNAM,SYSPRV) 2. Start up the server software. If you have not already done so, start the server software on the local node, using the NTDS START SERVER command. For example: $ NTDS START SERVER /CLUSTERNAME="Media" You must use the /CLUSTERNAME qualifier to define the cluster name for your OpenVMS Cluster. This is the name that Windows NT computers use to identify your OpenVMS Cluster when they connect to the disk services that it provides. 3. Start an active or standby disk service. Use the NTDS START SERVICE command to start the disk service on the local node. For example: $ NTDS START SERVICE "Sports" - _$ /CONTAINER=DISK$MEDIA:[NTDS$CONT]SPORTS.NTDS The /CONTAINER qualifier specifies the container file for the service. The parameter, in this example Sports, specifies the name you want to give to the service. This is the name that the Windows NT computer uses to identify the service when it connects to it. Configuring the Windows NT Computer to Connect to the Disk Service is the final step in setting up a virtual disk service for a Windows NT client. Log on to the Windows NT computer as an Administrator, and add the disk service to the configuration database. 7

8 When the OpenVMS Disk Services for Windows NT Administrator screen appears click Add and enter the cluster name and the service name, then click OK. Cluster Name Service Name DIGITAL OpenVMS Disk Services for Windows NT employs an open design that takes advantage of standard communications hardware, IP protocols (UDP and TCP/IP), and programming interfaces (TDI on Windows NT and PWIP on OpenVMS). This means NTDS easily fits into any environment with minimal additional expense or effort. 8

9 System Requirements Hardware Requirements The OpenVMS component runs on the OpenVMS Alpha hardware platform. The list of supported processors and hardware configurations is the same as those supported by OpenVMS and listed in the OpenVMS Alpha Operating System Software Product Description SPD (41.87.xx). The Windows NT component runs on any Intel or Alpha hardware platform that supports Windows NT Version 4.0 and is listed in the Microsoft s Hardware Compatibility List (HCL) for Windows NT Version 4.0 Disk Space Requirements: The approximate amount of space required on the OpenVMS and Windows NT system disks is as follows. OpenVMS - 40,000 blocks Windows NT - 8 MB Actual sizes may vary depending on the user's system environment, configuration, and software options. Cluster Environment: OpenVMS Disk Services for Windows NT is fully supported when installed on any valid, licensed OpenVMS Cluster configuration. OpenVMS Cluster configurations are fully described in the OpenVMS Cluster Software Product Description (29.78.xx). Software Requirements The following are the software requirements for DIGITAL OpenVMS Disk Services for Windows NT: OpenVMS Environment: OpenVMS Alpha Version 7.1 or 6.2 operating systems DIGITAL TCP/IP Services for OpenVMS Version 4.2. Windows NT Environment: Windows NT V4.0 Certified Configurations OpenVMS Disk Services is certified for up to fifty (50) concurrent connections to a single OpenVMS Cluster, such as 50 Windows NT systems each connecting to a different disk service on the OpenVMS Cluster. 9

10 Distribution Media The software is available on the OpenVMS Alpha Software Product Library CD- ROM. The documentation for DIGITAL OpenVMS Disk Services for Windows NT is available on the OpenVMS On-line Documentation Library CD-ROM. Software Licensing This software is furnished under the licensing provisions of Digital Equipment Corporation's standard terms and conditions. For more information about DIGITAL's licensing terms and policies, contact your local DIGITAL office. Centralized Storage on OpenVMS: Features and Benefits OpenVMS Scheduled "Back up" Windows NT applications and data can be backed up with existing OpenVMS backup routines. This reduces cost and maintenance time, because there are fewer storage activities requiring system management attention. OpenVMS Availability OpenVMS Disk Services provide a more highly available environment for storing Windows NT data or applications. All of the robust data protection measures of OpenVMS can be brought to bear ensuring the safety and availability of Windows NT data. Maximum Flexibility An organization gains increased control over storage allocation by dividing large OpenVMS disks into smaller virtual disks, and connecting them to different Windows NT servers. Future purchases of storage can be based on a user's requirements, instead of physical media packaging. 100% Compatibility Any Windows NT application that stores data on locally attached disks can store data on OpenVMS disks without modification. Windows NT applications can be installed directly on to the virtual disks. Grows with your needs OpenVMS Disk Services is based on a three-tiered computing design, and because the physical storage is hosted in the OpenVMS Cluster, disks can be readily added and made available to the Windows NT community. Leverage OpenVMS Investments OpenVMS Disk Services provides investment protection by allowing companies to utilize existing systems and storage capacity on OpenVMS to serve the growing number of Windows NT systems. 10

11 Worldwide Service and Support A business-critical computing environment requires comprehensive, flexible service and support. DIGITAL provides a single worldwide point of responsibility for all your multivendor service needs. DIGITAL s service professionals are ready to provide a total solution for your information infrastructure. Investing in the future OpenVMS Disk Services for Windows NT delivers the ability to store Windows NT data and applications on OpenVMS. However, DIGITAL does not intend to stop there. Future versions are actively being developed with an eye toward broader platform coverage, disaster tolerant solutions and optimization with Microsoft's Clustering model. DIGITAL is committed to supporting and extending the customer s investment in OpenVMS, the ideal partner for Windows NT in an enterprise client/server computing environment. DIGITAL OpenVMS Disk Services for Windows NT -- The smart, affordable way to maximize your storage investments! DIGITAL believes the information in this publication is accurate as of its publication date; such information is subject to change without notice. Contact your local DIGITAL office for the most up-to-date information. DIGITAL is not responsible for any inadvertent errors Digital Equipment Corporation. All rights reserved. DIGITAL, OpenVMS, PATHWORKS, and the DIGITAL logo are trademarks of Digital Equipment Corporation. Intel is a registered trademark of Intel Corporation. Windows NT is a trademark, and Microsoft is a registered trademark of Microsoft Corporation. 11