File System Administrator's Guide

Contents

Proprietary Notice

Documentation Log

Introduction

Chapter 1 File System Overview

1.1 Virtual Volume and File System
1.2 File System Types 1.2.1 Supercomputing File System 1.2.2 Network File System
1.3 SFS Structure 1.3.1 SFS 1.3.2 Asynchronous I/O Facility 1.3.3 Hybrid Special File (SFS/H)
1.4 Special Files 1.4.1 Types of Special Files 1.4.2 Creating Special Files 1.4.3 Access Dependent on Special File Specification

Chapter 2 Physical Device Management

2.1 Creating Special Files
2.2 Volume Format 2.2.1 Cylinder Classification 2.2.2 Volume Label
2.3 Disk Format

Chapter 3 Creating a File System

3.1 Disk Split
3.2 Creating a Virtual Volume
3.3 Creating a File System
3.4 Mounting and Unmounting File Systems 3.4.1 Mounting a File System 3.4.2 Unmounting a File System

Chapter 4 IAS and Virtual Volume

4.1 Intelligent I/O Accelerator Subsystem (IAS) 4.1.1 IAS Configuration 4.1.2 IAS Characteristics 4.1.3 IAS Extent Management
4.2 Disk Striping Facility 4.2.1 Control Method
4.3 Partition Management Facility
4.4 Multivolume Facility 4.4.1 Control Method 4.4.2 Virtual Disk Device Characteristics
4.5 Cache Control Facility

4.5.1 Cache Characteristics
4.5.2 Staging Unit
4.5.3 Cache Area Space Management
4.5.4 cache Daemon
4.5.5 Caching on a Root File System
4.5.6 Threshold Control Facility
4.5.7 Virtual Volume Cache Control Facility Guidelines
4.6 Reallocation Facility 4.6.1 Control Method 4.6.2 Reallocation Facility Guidelines
4.7 Virtual Volume Management Facility 4.7.1 Virtual Volume Labels 4.7.2 Virtual Volume Label Partitions
4.8 Special File Names 4.8.1 Virtual Disk Device 4.8.2 Partitions 4.8.3 Virtual Volume
4.9 IAS Structure and Operation 4.9.1 Virtual Disk Structure 4.9.2 Virtual Volume Structure 4.9.2.1 Virtual Volume Physical Configuration 4.9.2.2 Virtual Volume Performance Objective 4.9.3 Virtual Volume Definition Label Partitions 4.9.4 IAS Operating Condition
4.10 General Guidelines

Chapter 5 File System Construction

5.1 Overview
5.2 File System Construction Procedure 5.2.1 Creating Physical Device Special Files 5.2.2 Formatting Physical Devices 5.2.3 Setting Partitions 5.2.4 Setting Virtual Volume Label Partitions 5.2.5 Setting the Cache Capacity 5.2.6 Creating the Striping Disk Device 5.2.7 Creating Virtual Volumes 5.2.7.1 Setting Virtual Volume Configuration 5.2.7.2 Setting Attributes for Virtual Volume 5.2.8 Creating and Using File Systems
5.3 Using XMU 5.3.1 Usage and Characteristics of XMU 5.3.2 Example of XMU Configuration
5.4 SFS/H File System 5.4.1 Structure 5.4.2 Disk Striping 5.4.3 Construction 5.4.3.1 Kernel Configuration 5.4.3.2 Partition Definition 5.4.3.3 File System Creation 5.4.3.4 Use 5.4.4 Preallocate Function
5.5 Monitoring and Tuning 5.5.1 Operation Management Issues 5.5.2 Monitoring 5.5.2.1 File System Operation Status 5.5.2.2 Tuning and Reconfiguration 5.5.2.3 Actual Device Operation Status 5.5.3 Tuning 5.5.3.1 File System Buffer 5.5.3.2 Virtual Volume Extent 5.5.3.3 Virtual Volume Cache 5.5.4 Case Studies

Chapter 6 File System Management

6.1 Disk Monitoring
6.2 File System Repair

6.2.1 The fsck Command
6.2.2 The fsdb Command

6.2.2.1 Locate the Current Address
6.2.2.2 Display Current Contents
6.2.2.3 Change Current Contents
6.2.2.4 Miscellaneous fsdb Functions
6.3 Resource Management
6.4 Automatic File System Mounting
6.5 Data Writing Consistency
6.6 sync Daemon
6.7 IAS Management

6.7.1 devinfo Command
6.7.2 cache Daemon
6.8 Backup and Restore 6.8.1 File System Backup/Restore 6.8.2 Backup/Restore Files and Directories
6.9 Cache Trouble
6.10 Managing the SFS/H File System 6.10.1 Checking the SFS/H File System 6.10.2 Notes on Using SFS/H 6.10.2.1 File Size 6.10.2.2 Others

Chapter 7 File Recovery

7.1 Overview
7.2 System Design 7.2.1 Hardware Configuration 7.2.2 System Operation 7.2.2.1 VVLDEV Setting and Operation 7.2.2.2 Volume Management Using Logical Unit Numbers 7.2.2.3 Operation Using Multiple Root Volumes 7.2.2.4 Example of System Construction
7.3 Backup Operations 7.3.1 Backup Operation Principles 7.3.2 Center Operations 7.3.2.1 Root Volume Backup 7.3.2.2 Data Volume Backup 7.3.3 End User Operation 7.3.4 Caution
7.4 Recovery Operations 7.4.1 Effect on the System 7.4.1.1 Root Volume 7.4.1.2 Data Volume 7.4.1.3 XMU Virtual Disk Device Faults 7.4.1.4 Faults in VVLDEV 7.4.1.5 Virtual Volume Faults 7.4.1.6 File System Faults 7.4.2 Fault Notification 7.4.3 Fault Identification 7.4.4 Recovery Preparations 7.4.5 Recovery 7.4.5.1 Recovery from Disk Device Faults (Total Device Faults) 7.4.5.2 Recovery from Striping Disk Faults 7.4.5.3 Recovery from XMU Virtual Disk Device Faults 7.4.5.4 Recovery from VVLDEV Faults 7.4.5.5 Recovery from Virtual Volume Faults 7.4.5.6 Recovery from File System Faults

Chapter 8 Disk Recovery

8.1 Overview 8.1.1 Protection and Maintenance 8.1.2 I/O Error Recovery 8.1.3 Device Blockage Error Recovery 8.1.4 HDA Replacement 8.1.5 Indication of Error Locations in SUPER-UX and IOX
8.2 Protection and Maintenance
8.3 I/O Error Recovery (No Device Blockage) 8.3.1 Error Separation and Block Error Recovery 8.3.1.1 File System Reconstruction 8.3.1.2 File System Recovery 8.3.1.3 File Restore 8.3.1.4 Disk Replacement 8.3.1.5 Device Blockage Error Recovery
8.4 File Recovery Procedure for SCSI Disk Device/Array Disk

Chapter 9 Inode Duplication Facility

9.1 Purpose
9.2 Outline 9.2.1 Devices to Be Duplicated 9.2.2 Registering the Duplication 9.2.3 Duplication Control
9.3 Commands
9.4 Using the Duplication Facility 9.4.1 Setting the Duplication 9.4.2 Canceling the Duplication 9.4.3 Reconstructing the File System 9.4.4 Relationship with Existing Commands 9.4.4.1 Backup Commands 9.4.4.2 Existing IOS Commands
9.5 Error Handling
9.6 Error Types and Recovery 9.6.1 Isolating Errors 9.6.2 Recovery when the Master VD Is Closed 9.6.3 Recovery when the Copy VD Is Closed 9.6.4 Recovery when a Copy VD Error Occurs (Master VD Closed) 9.6.5 Recovery when a Master VD Error Occurs (Copy VD Closed) 9.6.6 Recovery when an Error Occurs Outside the Duplication Range 9.6.7 Recovery when an Error Occurs in VVL
9.7 Notes

Appendix A fsck Error Messages

A.1 Running fsck

A.1.1 Initialization Phase
A.2 General Errors
A.3 Phase 1: Check Blocks And Sizes A.3.1 Rescan For More DUPs
A.4 Phase 2: Check Path Names
A.5 Phase 3: Check Connectivity
A.6 Phase 4: Check Reference Counts
A.7 Phase 4b: Check ACL Bit Map
A.8 Phase 5: Check Free List
A.9 Phase 5b: Check Free ACL List
A.10 Phase 6: Salvage Free List
A.11 Phase 6b: Salvage Free List
A.12 Cleanup Phase

Appendix B alcck Messages

B.1 Running alcck
B.2 Initialization Phase
B.3 Phase 1: Check Virtual Volume Label
B.4 Phase 2: Check VVTOC Management Information
B.5 Phase 3: Check Free Area Information
B.6 Phase 4: Check Allocation Maps
B.7 Phase 5: Check Bit Map
B.8 Phase 6: Check Statistical Information
B.9 Phase 7: Update VVTOC

Appendix C Array Disk Unit

C.1 N7763 Magnetic Disk Unit
C.2 Device Configuration C.2.1 N7763 Magnetic Disk Unit C.2.1.1 Subsystem C.2.1.2 Array Modules C.2.1.3 Slave C.2.1.4 Facilities C.2.1.5 Device Specifications C.2.1.6 Physical Block Size C.2.1.7 Facility Address C.2.1.8 Subpartitions C.2.1.9 Array Console C.2.2 N7764 Magnetic Disk Unit C.2.2.1 Disks C.2.2.2 Directors C.2.2.3 Slave C.2.2.4 Facilities C.2.2.5 Physical Block Size C.2.2.6 Facility Address
C.3 Using the Array Disk Unit

C.3.1 Preparation

C.3.1.1 Facilities
C.3.1.2 Slave
C.3.1.3 Alternative Path Function for Array Disks
C.3.1.4 fmthard(1M)
C.3.1.5 Striping Disk
C.3.1.6 Virtual Volume

Appendix D Backing Up and Restoring Disks in UP-UX

D.1 Creating a Backup Table D.1.1 Storing Partition Information D.1.2 Storing Entire Disk Information
D.2 Making a Backup D.2.1 Backing Up a Partition D.2.2 Backing Up an Entire Disk
D.3 Restoring a Backup D.3.1 Restoring a Partition D.3.2 Restoring an Entire Disk

Appendix E Cache Algorithm

Appendix F Quick Reference

F.1 Administrator Commands for Virtual Volumes
F.2 Extents of the Virtual Volume

Appendix G SX-MFF

Figures

1-1 File System Overview
1-2 SFS Structure
1-3 SFS Inode Structure
1-4 Asynchronous I/O Diagram
2-1 Physical Disk Device Cylinder Allocation
3-1 Virtual Volume Configuration Definition
4-1 Virtual Volume and Virtual Disk Devices
4-2 IAS Function Diagram
4-3 Information Exchange Between IAS and User
4-4 Extent Relationship of IAS
4-5 Disk Striping Facility
4-6 Partition Management
4-7 Virtual Volume Example
4-8 Cache Control Facility Configuration
4-9 Reallocation of Disk Space
4-10 IAS Configuration
5-1 Operation Cycle of the Ideal File System
5-2 Relationship Between Performance and Space Efficiency for Each File System
5-3 Structure of the SFS/H File System
5-4 SFS/H Striping
7-1 System Construction
8-1 Protection and Maintenance Procedure
8-2 I/O Error Separation and Block Error Recover
8-3 Superblock/VVTOC Error Recovery Procedure
8-4 Inode/Linked List Block/Indirect Cluster Error Recovery Procedure
8-5 Restoring Files
8-6 Disk Replacement
8-7 Device Blockage Recovery
8-8 SCSI Disk Device/Array Disk File Recovery Procedure

Tables

4-1 IAS Extents
4-2 devinfo(1M) Command Options
5-1 Construction of a File System with the Cache Disabled
5-2 Construction of a File System with the Cache Enabled
5-3 Cache Hit Ratios
6-1 fsck(1M) Command Options
6-2 Current Operators and Symbols
6-3 Current Print Options for Display Format
6-4 Current Print Options
6-5 Equal-Sign Operators for Current Content
6-6 Symbols that Change Data Types of fsdb
6-7 Symbols that Show Directory Entry Fields
6-8 Symbols that Show Inode Fields
6-9 Current Save and Restore Symbols
6-10 Write Data Dependent on Write-on-Close Function
6-11 Backup Strategies 1
6-12 Backup Strategies 2
7-1 Backup/Restore Commands
7-2 Recovery Method
C-1 Facility Types
C-2 Assignment of Facility Addresses in One Subsystem
C-3 Track and Cylinder Sizes
C-4 Subpartition Sizes
C-5 Facility Address Assignments
F-1 Administrator Commands for Virtual Volumes
F-2 Extents of the Virtual Volume
G-1 Sub-partition Sizes of SX-MFF