MaxAttach NAS 6000 RAID Reconfiguration Description This document describes procedures required in order to create/modify/delete RAID configurations on the NAS 6000 Storage Server. This document contains instructions for changing the RAID type on User Data Volume 1 without damaging either operating system or backup operating system partitions. Improper modification of User Data Volume 1 may result in complete loss of the operating system and backup operating system partitions, recoverable only by on-site repair or depot service. Related Documents: NAS 6000 Administration Guide: Chapter 11 – Appendix – Disk Array RAID Concepts. NAS 6000 Installation and Configuration Guide: Chapter 7. Answer NAS 6000 Base Unit Factory Default Settings: GAM Disk Array GAM Logical Drive RAID Type Drive Letter Usage Options for Array Reconfiguration Usable Space In Bytes Usable Space Gigabytes 0 0 RAID 0+1 C: OS None 7,309,540,000 6.97 GB 0 1 RAID 0+1 D: Backup OS None 14,659,280,000 13.9 GB 0 2 RAID 5 (6 Drives) E: User Data Volume 1 RAID Type modification only 763,649,740,000 728 GB 1 3 RAID 5 (6 Drives) F: User Data Volume 2 RAID Type modification deletion/creation of disk array 800,310,072,000 763 GB Definitions: Array A collection of physical hard disk drives. Logical Drive A collection of drives within an array and assigned RAID type, which are presented to the operating system as logical devices. Drive Letter Microsoft Windows Volume number. The Windows volume is created from the logical drive. General Guidelines: Tools for the creation, modification and deletion of Arrays, Logical Drives and Windows volumes: Mylex GAM is provided for modifications to array and logical drive configurations Windows Disk Management is provided for Windows volume creation (as noted by drive letter). Significance of the base array - Array 0 Array 0 is pre-configured as RAID type 0+1and contains the primary and backup copies of the NAS 6000 operating system (Windows volumes C and D respectively). GAM software does not, however, prevent users from modifying Array 0. Therefore, pay special attention to the following restrictions: Do not delete or reconfigure Array 0. Do not delete logical drives from or add logical drives to Array 0. Plan the array reconfiguration Allocate sufficient time for any array reconfiguration activity and always backup the data before beginning an array reconfiguration. Do not begin new array configuration activity until the previous activity is completed. The time required to complete any array initialization is more dependent upon the RAID type and size of the hard drives, and less on the system hardware and OS platforms. For example, a RAID5 array with six 160 GB drives requires about 14 hours to initialize, whereas a RAID 0 configuration may only take 10 minutes or less. Changing a RAID type on an array or deleting an array will delete all of the data on that array Resize an existing array You can expand an array by adding hard drives. Once an array has been created, however, you cannot reduce the array size by removing hard drives associated with that array, because data is spread across all the hard drives within that array. When adding hard drives to an existing array, logical drives must be assigned to the newly available disk space in order to utilize the extra disk space. The expansion of an existing array automatically starts the rebuild process for the entire array. This process does not, however, destroy any existing data on the array. The optimal RAID5 array configuration A six-disk RAID5 array offers the optimum I/O performance, fault tolerance and the lowest disk space overhead (83% efficiency) for data redundancy. If the array is set up as a RAID5 configuration, we recommend that no more than six physical drives be included, as this will decrease write I/O performance. Order of creation for Arrays, Logical Drives and Windows volumes Before creating a new array, ensure that the previous array is fully propagated with logical drives. On each array, the Logical Drive numbers are automatically created in ascending order. Windows volumes are created based on the logical drives. For example, a Windows volume can be a partition of a logical drive or a single logical drive. Order of deletion for Arrays, Logical Drives and Windows volumes In order to delete a logical drive, the Windows volume associated with that drive must be deleted first. Logical drives are deleted in descending order. Before deleting an array, all the logical drives created on the array must be deleted first. Do not move drives from one bay to another. The hardware RAID controller uses the bay location to calculate striping and redundancy. Moving disk drives to different bays would confuse the RAID controller and could result in data loss. Do not delay failed drive replacement. Depending on how you configure RAID 1 or 5, in the event one drive fails, the next drive failure could result in data loss. Defer any array configuration activity until the drive is replaced. Accessing the Mylex GAM through Terminal Services The GAM RAID configuration tool is available through Terminal Services on the MaxAttach NAS 6000. All of the instructions described in the following sections assume that the user has access to Terminal Services. A Terminal Services client interface is available as a plug-in for an Internet Explorer web browser. This plug-in can be automatically downloaded from the NAS 6000 server. The following instructions explain how to obtain the Terminal Services Plug-in for the first time: Launch Internet Explorer to access the NAS 6000 web user interface (web UI) with the address. (e.g., http://servername) Login as Administrator Click the Administer this server appliance link. If the desktop web browser is Microsoft Windows Internet Explorer 5.5 or later, steps 5 and 6 apply otherwise skip to step 7. If prompted for a security certificate, click on the OK button. Login as Administrator (via https protocol) On the Welcome page, click on the blue Maintenance button. On the Maintenance page, click on the Terminal Services item. A Security Warning window will appear the first time a client web browser is used to launch the Terminal Services plug-in. Click on the Yes button to install the Terminal Services Active X control. The Terminal Services plug-in will be installed and a login window will appear for access to the Windows desktop connected to the server. Tips on Using the GAM Background vs. foreground initialization of logical drive. Upon creating a new logical drive, the initialization process occurs in the background by default. Users do, however, have the option of changing the logical drive initialization process to occur in the foreground. Although the background initialization process takes longer than foreground initialization, the logical drive is available to users during the background initialization process, whereas it is unavailable for use during foreground initialization. Background initialization creates the redundant parity data while preserving the user data; foreground initialization writes zeros to all data space (and parity stripes). RAID Configuration Options and Associated Number of Drives Possible RAID Type Selections in the Mylex GAM Menu Number of Hard Drives in an Array JBOD 1 Only RAID 0 1 or More RAID 0+1 * 3 or More RAID 1 2 Only RAID 5 3 or More The maximum number of drives in any array 16 * NOTE: RAID 0+1 is possible on an odd number of drives as the controller mirrors stripes of data, not drives, in this configuration. Storage Re-configuration Options: Drive C: (Array 0): Contains the primary Windows 2000 Server OS, therefore there is no re-configuration option available. Drive D: (Array 0): Contains the backup Windows 2000 Server OS, therefore there is no re-configuration option available. Drive E: (Array 0): The existing RAID 5 logical disk can be changed to RAID 0 or RAID 0+1. This logical disk (Array 0) cannot become a JBOD configuration as the JBOD configuration is restricted to one disk per array and Array 0 has six disks. A RAID type conversion will delete all of the data stored on drive E: Drive F: (Array 1): The existing RAID 5 logical disk may be changed to JBOD, RAID 0 or RAID 0+1 arrays. A RAID type conversion will delete all of the data stored on drive F: Expansion Units: The NAS 6000 expansion units are factory-configured as JBOD, but may be changed to RAID 0, 0+1 or 5. NOTE: The following instructions for RAID reconfiguration apply to the NAS 6000 base unit as well as expansion units. Instructions for Entering GAM: Inspect the NAS 6000 server for disk subsystem failures and take corrective actions as necessary. From the Terminal Services session, on the Windows desktop, click on Start �¨ Programs �¨ Mylex Global Array Manager (GAM) Client. In the GAM, select the Administration pull down menu and select Sign In. Enter the User name as gamroot. The password is blank by factory default. Click on the Sign-On button. In the GAM, select the Administration pull down menu and select RAID Assist On the Welcome tab of the RAID Assist interface, click on the Manual Configuration button. ! WARNING ! Do not select any other buttons. Selecting any of the other buttons may result in data loss! Instructions for Removing a Logical Drive in an Array: Backup user data. Follow the Instructions for Entering GAM above. In the Manual Configuration Window, in the Data Overwrite Method box, click on the Edit Configuration button. In the Manual Configuration/Edit Configuration Window, Tab #2, Disk Array will appear. Click on the Tab #3, Logical Drives to continue. Click on the Delete Drive button to remove it. This action will remove the logical drive with highest number. Click on the Apply button for the changes to take effect. A warning message from the GAM will appear with the text: Warning: During Edit Configuration, your actions have resulted in changes to one or more existing logical drives. If you proceed, all data on the affected logical drive(s) and your existing configuration will be lost. Do you want to proceed? Click on the Yes button to continue. A second warning message will appear from the GAM: Warning: Changing configuration is data destructive! If you want to proceed, confirm by typing the word yes in the text box provided and click on the Yes button. A window will appear with the title bar Physical Device Options. In this window will be a list of the available drives for new arrays. Click on the Cancel button. Do not attempt to change a Physical Device Option in this window. The RAID assist session ends at this point, leaving the user with the GAM Controller view on the desktop. If all of the logical drives on this array have been deleted, the drives in the unallocated array will be available for re-allocation. Proceed to the following section if you wish to create new arrays and logical drives from the unallocated array. Instructions for New Array and Logical Drive Creation: Backup user data. Follow the Instructions for Entering GAM above. In the Manual Configuration Window, in the Data Overwrite Method box, click on the Edit Configuration button. In the Manual Configuration/Edit Configuration Window, Tab #2, Disk Array will appear. Click on the Add Array button. Drag and drop drives from the Unused Disk Drives pool to the newly created array. ! WARNING ! Do not drag and drop disks from any existing arrays. Performing this operation will clear all of the existing logical drives, including the Operating System and Backup Operating System, which will severely impact the stability of the NAS 6000. If this operation is accidentally performed, please click on the Cancel button to abort the operation. In the Manual Configuration/Edit Configuration window, select the Tab #3, Logical Drives. Notice the New Box displayed above the existing drives. In this box, set the desired RAID level, set the capacity (leave this at the default if only one logical drive will be created on this array) and select the Write Cache (enable it). Check the Init drive option if a data foreground initialization (writes zeros all blocks) is desired. If the Init drive box is not checked, a background initialization (non data-destructive generation of parity information) will occur automatically. Do not change the Stripe Size or the Cache Size. Select the Add Drive button to move the new drive into the list of drives. Select the Apply button to write the changes. NOTE: All changes become permanent with this selection. Select the Apply button for every logical drive configured. Do not configure additional logical drives before selecting the Apply button. The GAM will display a warning box with the text: Warning: Changing configuration is data destructive! If you want to proceed, confirm by typing the word yes in the text box provided and click on the Yes button. A window will appear with the title bar Physical Device Options. In this window will be a list of the available drives. Do not attempt to change a Physical Device Option in this window. Click on the Cancel button. The RAID assist session will end at this time, leaving the user with the GAM Controller view on the desktop. If the Init drive (in the foreground) option was selected, an Initialize Status window will appear. It is safe to use the Close button while the foreground initialization is occurring. Initialization progress can be checked later under the GAM View/Initialize Status menu option.