EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11

Transcription

1 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide P/N REV A01 EMC Corporation Corporate Headquarters: Hopkinton, MA

2 Copyright EMC Corporation. All rights reserved. Published August, 2008 EMC believes the information in this publication is accurate as of its publication date. The information is subject to change without notice. THE INFORMATION IN THIS PUBLICATION IS PROVIDED AS IS. EMC CORPORATION MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WITH RESPECT TO THE INFORMATION IN THIS PUBLICATION, AND SPECIFICALLY DISCLAIMS IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Use, copying, and distribution of any EMC software described in this publication requires an applicable software license. For the most up-to-date regulatory document for your product line, go to the Technical Documentation and Advisories section on EMC Powerlink. For the most up-to-date listing of EMC product names, see EMC Corporation Trademarks on EMC.com. All other trademarks used herein are the property of their respective owners. 2 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

3 Contents Preface Chapter 1 Chapter 2 Chapter 3 Introduction DiskXtender for UNIX/Linux Storage Manager overview DXUL-SM features NFS and FTP protocols File migration, purging, and caching Transparent access to files Using the Network File System Protocol NFS overview NFS commands Common NFS replies and errors Getting started Display mounted file systems How to determine file location Retrieving files from tape Sample NFS session Using the File Transfer Protocol FTP overview Authentication DiskXtender FTP commands FTP replies and errors Getting started How to establish an FTP connection to a remote computer 28 How to log in to the DXUL-SM system EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide 3

4 Contents Retrieving files from tape How to use the quote wait command How to use the quote stage command How to determine whether a file is on disk or tape Sample FTP Session Chapter 4 Appendix A Appendix B Trash Can Trash can description Trash can limitations How to retrieve files FTP Commands UNIX commands for FTP FTP partial read DiskXtender commands for FTP FTP Reply Codes Common status replies FTP replies Glossary 4 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

5 Preface As part of an effort to improve and enhance the performance and capabilities of its product lines, EMC periodically releases revisions of its hardware and software. Therefore, some functions described in this document may not be supported by all versions of the software or hardware currently in use. For the most up-to-date information on product features, refer to your product release notes. If a product does not function properly or does not function as described in this document, please contact your EMC representative. Audience This document is part of the EMC DiskXtender for UNIX/Linux Storage Manager release 2.11 documentation set, and is intended for use by system administrators. Readers of this document are expected to be familiar with the following topics: Their organization s data archiving strategy, in particular: Average archived file size. Anticipated total number of files and total bytes to be archived. File access norms: frequency of access during creation, edit, and archive phases. Special file requirements, such as shorter access times, multiple fail-safe copies, and optimal file stub size. Backup strategies for data in the file systems. The network details of all computer systems and hardware devices to be used, including: EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide 5

6 Preface IP addresses. TCP/IP routing information. Switch, router, firewall, and network-attached device configurations. The administration details of all involved storage devices. Related documentation Conventions used in this document Related documents include: EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 Administration Guide EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 Installation Guide EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 System Environment Manager Guide EMC AutoStart Module for EMC DiskXtender UNIX/Linux Storage Manager EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 Release Notes EMC uses the following conventions for special notices. Note: A note presents information that is important, but not hazard-related.! CAUTION A caution contains information essential to avoid data loss or damage to the system or equipment.! IMPORTANT An important notice contains information essential to operation of the software. 6 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

7 Preface Normal Bold Italic Courier Courier bold Typographical conventions EMC uses the following type style conventions in this document: Used in running (nonprocedural) text for: Names of interface elements (such as names of windows, dialog boxes, buttons, fields, and menus) Names of resources, attributes, pools, Boolean expressions, buttons, DQL statements, keywords, clauses, environment variables, functions, utilities URLs, pathnames, filenames, directory names, computer names, links, groups, service keys, file systems, notifications Used in running (nonprocedural) text for: Names of commands, daemons, options, programs, processes, services, applications, utilities, kernels, notifications, system calls, man pages Used in procedures for: Names of interface elements (such as names of windows, dialog boxes, buttons, fields, and menus) What user specifically selects, clicks, presses, or types Used in all text (including procedures) for: Full titles of publications referenced in text Emphasis (for example a new term) Variables Used for: System output, such as an error message or script URLs, complete paths, filenames, prompts, and syntax when shown outside of running text Used for: Specific user input (such as commands) Courier italic Used in procedures for: Variables on command line User input variables < > Angle brackets enclose parameter or variable values supplied by the user [ ] Square brackets enclose optional values Vertical bar indicates alternate selections - the bar means or { } Braces indicate content that you must specify (that is, x or y or z)... Ellipses indicate nonessential information omitted from the example EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide 7

8 Preface Where to get help Your comments EMC support, product, and licensing information can be obtained as follows. Product information For documentation, release notes, software updates, or for information about EMC products, licensing, and service, go to the EMC Powerlink website (registration required) at: Technical support For technical support, go to EMC Customer Service on Powerlink. To open a service request through Powerlink, you must have a valid support agreement. Please contact your EMC sales representative for details about obtaining a valid support agreement or to answer any questions about your account. Comments and suggestions about our product documentation are always welcome. To provide feedback: 1. Go to: 2. Click the Feedback link. 8 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

9 1 Introduction This chapter contains the following sections: DiskXtender for UNIX/Linux Storage Manager overview DXUL-SM features NFS and FTP protocols File migration, purging, and caching Transparent access to files Introduction 9

10 Introduction DiskXtender for UNIX/Linux Storage Manager overview EMC DiskXtender for UNIX/Linux Storage Manager (DXUL-SM) software works with a UNIX/Linux system to provide scalable, hierarchical file storage to UNIX and Linux users. A typical UNIX system provides a variety of storage media that can be used for both short-term and long-term storage. Figure 1 on page 10 shows a UNIX configuration. Figure 1 Typical UNIX system configuration In a UNIX environment, the system administrator is responsible for: Performing regular backups of files stored on short-term storage, such as magnetic disks in case of disk failure. These backups are generally stored on long-term storage such as tapes. Maintaining adequate free space for routine operations on the disks. When the disks are full, users must move their least-used files from disk to tape media. Once these files have been moved, they no longer appear in the user directory and must be separately cataloged. As time passes and users work with larger numbers of files, it becomes increasingly difficult to keep track of them. 10 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

11 Introduction To overcome limitations, such as moving least-used files to tape media, the DXUL-SM software automatically manages files in a storage media hierarchy. The software moves files off the disk and automatically performs file backups. The DXUL-SM software creates a link to all files, including those stored on offline tapes. With these links, files stored on tape still appear in the user directory and can be easily copied back to the disk when needed. The DXUL-SM software provides virtually unlimited storage space, and provides transparent access to all files, regardless of their physical location. DiskXtender for UNIX/Linux Storage Manager overview 11

12 Introduction DXUL-SM features The DXUL-SM software includes the following features: An interface that appears similar to a standard UNIX file system. Automatic file migration caching and purging. Access through industry-standard network file system (NFS) and File Transfer Protocol (FTP) interfaces. Unlimited file size and filename length. Protection from accidental file deletion. Implements a centralized library management solution for easier administration, increased utilization and a lower cost of ownership using ACSLS Manager software. 12 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

13 Introduction NFS and FTP protocols The DXUL-SM software manages access to files through NFS or FTP. To users who access the DXUL-SM software through NFS, the DiskXtender file system is a transparent extension of the UNIX file system. Users interact with their files by using standard UNIX commands and processes. To users who access the DXUL-SM software through FTP, the standard FTP interface includes an extended set of FTP commands and capabilities. Through FTP, the user can move and access files, set file permissions with special commands, create symbolic links, and cache files. Chapter 3, Using the File Transfer Protocol, provides more information on the use of FTP to manage files on the DiskXtender file system. NFS and FTP protocols 13

14 Introduction File migration, purging, and caching While maintaining the appearance of a UNIX file system, the DXUL-SM software continuously manages user files in the storage hierarchy. The DXUL-SM software uses disks attached to the UNIX system as a disk cache. Storage on disks is reserved for files that have been accessed most recently. Files are regularly moved within the storage hierarchy through the DiskXtender processes of migration, purging, and caching. Migration is the copying of files from the disk cache (disk) down the storage media hierarchy onto another media level as shown in Figure 2 on page 14. Figure 2 DiskXtender file migration flow At regular time intervals, or when disk cache space use exceeds preset limits, all files that have not been previously migrated are migrated. After migration, copies of migrated files exist on both the disk cache and the lower level of the hierarchy. 14 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

15 Introduction Purging occurs when files on the disk cache exceed a preset percentage of the disk cache space, called the high water mark. Files which have been migrated to a lower level in the hierarchy are eligible for purging from the disk cache. Purging files from the disk cache continues until a preset percentage of free space, called the low water mark, is reached on the disk cache. File migration, purging, and caching 15

16 Introduction Transparent access to files The DXUL-SM software maintains a link to all files, regardless of the level of storage hierarchy on which they are located. The user directory contains these links. When a user requests access to a file that has been purged from the disk cache, the DXUL-SM software caches, or copies, the file directly back to the disk cache from the level to which the file was previously migrated as shown in Figure 3 on page 16. Figure 3 DiskXtender file caching Users may notice some delay during the caching process, depending on the type of storage media on which the file is located. Once the file is available on the disk cache, the user regains full access. 16 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

17 2 Using the Network File System Protocol This chapter contains the following sections: NFS overview NFS commands Getting started Sample NFS session Using the Network File System Protocol 17

18 Using the Network File System Protocol NFS overview The NFS connects file systems among independent computers. The NFS enables access to DiskXtender files and directories from a remote computer, and makes the DiskXtender file system appear to be part of the local file system, as shown in Figure 4 on page 18. Figure 4 NFS access 18 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

19 Using the Network File System Protocol NFS commands The NFS is transparent and uses only standard UNIX commands. The NFS-mounted file systems function in the same manner as a standard UNIX file system. You can copy files to and from the remote file system by accessing the appropriate directory. The relevant man pages provide more information on NFS and can be accessed by typing: man nfs man -k nfs Common NFS replies and errors The NFS uses the same replies and error messages that are displayed by the UNIX file system with two exceptions: When the link between the local computer and the remote server is broken. When a requested file resides only on tape. In these cases, the following message may appear: When the file system is mounted by using the NFS version 2: NFS server not responding, will try again When the file system is mounted by using the NFS version 3: File temporarily unavailable on the server, retrying... The computer continues to access the remote server until it is successful. If the file system is mounted by using the NFS version 2, commands that reference a file being cached may queue behind the original request that cached the file. As a result, these commands appear to stop responding. To stop a process that is not responding, press Ctrl-C. NFS commands 19

20 Using the Network File System Protocol Getting started Before you can access the remote DiskXtender file system with the NFS, the system administrator or a superuser must attach a remote file system to the local file system by using the UNIX mount command: mount -o intr,port=<diskxtender NFS Server Port Number> <IP Address of DiskXtender Host>:/DISKXTENDER/ <Mount Point> Once the remote file system is mounted, access to it is transparent. You can use UNIX commands to manipulate the remote DiskXtender file system. Display mounted file systems To display a list of all file systems currently mounted on the local computer, type the mount command: mount If the file system to be accessed has been mounted, type the UNIX commands to access its files and directories. How to determine file location The sticky bit in the files Permission field indicates whether a file exists on disk and is available for immediate retrieval, or whether it exists only on tape. The sticky bit is set for all files which exist only on tape. To determine the location of a file, type: ls -l The output of the ls -l command is similar to the following: -rw-rw-r-t 1 u1 user 4165 Feb 23 21:16 file1 The letter T indicates that the sticky bit is enabled and file1 is located on tape. To use the sticky bit for its intended purpose, rather than to indicate file location, contact the system administrator for further assistance. Retrieving files from tape Because remote and local files appear the same, it is often difficult to distinguish between files on tape (remote) and files on disk (local). 20 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

21 Using the Network File System Protocol The primary difference between accessing files from the local file system and accessing files from the DiskXtender file system by the NFS protocol is the speed at which files are retrieved. For example, when you use a command, such as vi, to edit a file stored on tape, there is a noticeable increase in access time when compared to using the vi command to edit a file stored on disk. How to interrupt a process that Is accessing a file! If an attempt to access a file does not finish within a reasonable time, do the following: 1. Stop the process by pressing Ctrl-C. The files being accessed continue to be cached from tape to disk on the remote computer. 2. Once the files have been cached to disk, attempt to access the file again. IMPORTANT A process can be interrupted only if the DiskXtender file system is mounted with version 3 or version 2 as interruptible. If issuing the interrupt command does not stop the process, contact the system administrator for further assistance. Getting started 21

22 Using the Network File System Protocol Sample NFS session In this sample NFS session: /usr/local/bob is the local directory. /usr/remote/bob is a remote directory that has been mounted with read/write access on the local directory, /usr/mnt/bob. 1. To display all file systems as mounted and the access permissions for each mounted system, type: mount remote: /usr/remote/bob on /usr/mnt/bob nfs (rw) 2. To determine the current directory, type: pwd /usr/local/bob 3. To change to the /usr/mnt/bob directory, type: cd /usr/mnt/bob 4. To verify that the current directory is /usr/mnt/bob, type: pwd /usr/mnt/bob 5. To display the files in the /usr/mnt/bob directory, type: ls -a....trash file1 file2 The user is initially in the local directory /usr/local/bob and then changes to the remote directory through the local mount point /usr/mnt/bob. 6. To display the files and their attributes in the current remote directory, type: ls -l 22 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

23 Using the Network File System Protocol The output of this command appears: drw u2 user 1024 Feb 23 20:00.trash -rw------t 1 u1 user 4165 Feb 23 21:16 file1 -rw u1 user 2458 Feb 23 21:16 file2 where: An uppercase T at the end of the permissions indicates that the file is on archive media and that the execute bit in the permissions has not been set. A lowercase t indicates that the file is on archive media and that the execute bit in the permissions has been set. For more information on permission bits and their meaning, the UNIX man page for the ls command provides information. 7. To copy file3 from the local directory to the remote directory, type: cp /usr/local/bob/file3 file3 8. To verify that file3 has been copied, type: ls -a....trash file1 file2 file3 The local file file3 has been copied to the remote directory. 9. To copy file1 from the current remote directory to the local computer and rename it to newfile, type: cp file1 /usr/local/bob/newfile Because the user is currently in the remote directory, it is not necessary to provide a full pathname for the remote directory. 10. To verify that the file is actually copied into the local directory, navigate to /usr/local/bob directory and type: ls file3 file4 newfile Sample NFS session 23

24 Using the Network File System Protocol 24 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

25 3 Using the File Transfer Protocol This chapter contains the following sections: FTP overview Getting started Retrieving files from tape Sample FTP Session Using the File Transfer Protocol 25

26 Using the File Transfer Protocol FTP overview FTP is an industry-standard method to transfer files to and from a remote computer system. Appendix A, FTP Commands, provides a list of commonly used FTP commands. All operating systems can access DXUL-SM file systems with a standard FTP client. Authentication DXUL-SM supports secure control channel feature for FTP interface to secure authentication and command transmission over the network. The control channel is compliant with SSL protocol version v2 and v3. With this, user authentication, commands from FTPS clients (SSL enabled FTP clients) to uftpd of DXULSM and the 'reply' messages from uftpd to the FTPS clients will be encrypted. For example: During login, FTPS clients will send an AUTH command followed by auth method 'TLS' as an authentication method. The TLS auth method is common for both SSL and TLS protocols. The actual protocol level (SSL v2, SSL v3 or TLS) will be decided between the client and server during the handshake. After validating the auth type method in FTP server sent by the FTPS client, the uftpd will send a reply as 'AUTH TLS OK.' with 234 as the reply code, if the auth method is TLS. After this, the FTPS client and uftpd will do a SSL handshake. The login will be successful only after the completion of these security negotiations. DXULSM FTP server supports both standard FTP and FTPS clients. If a client sends AUTH TLS command, DXULSM FTP server would recognize that the client is SSL enabled and proceed for SSL negotiations. Suppose user uses the standard FTP client then the SSL negotiation will not take place and the communication between FTP client and FTP server is not secure over the network. Depending on the requirements, user can access the DXULSM FTP either by standard FTP clients (which are not SSL enabled) or by using the standard FTPS clients (which are SSL enabled) to avail the secure control channel communication with the DXULSM FTP server. 26 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

27 Using the File Transfer Protocol DiskXtender FTP commands The DXUL-SM software expands on FTP features through the use of the quote site and quote commands. Depending on the FTP client software, the format of these commands is either of the following: quote site command (used mostly by older versions of FTP client software) quote command (used mostly by newer versions of FTP client software) On most systems, these commands are case-insensitive, and should not be abbreviated. The quote help command displays information about the commands on the remote FTP server: To get a list of valid commands on the remote FTP server, type: quote help To get help on a specific remote command, type quote help followed by the command name: quote help command_name To read files partially, execute the offlen command followed by a get request: ftp> quote offlen <file offset> <length in bytes> <filename> Table 3 on page 47 provides complete details on all DiskXtender FTP commands. FTP replies and errors When an FTP command is entered, a corresponding reply is returned. The reply indicates whether the command is accepted, being processed, or rejected. An FTP reply consists of a three-digit code followed by a brief description of the result. Appendix B, FTP Reply Codes, provides information on FTP replies. FTP overview 27

28 Using the File Transfer Protocol Getting started Before you can use FTP to access files on the DiskXtender file system, you must establish an FTP connection from the local computer to the remote computer where the files are located. To access a remote computer by using FTP, you must have a valid remote login name and password. If you do not have a remote login name and password, contact the system administrator. How to establish an FTP connection to a remote computer on page 28 provides instructions on connecting to a remote computer. After establishing a connection to the remote computer, you must then log in to the DXUL-SM system. How to log in to the DXUL-SM system on page 29 provides more information. How to establish an FTP connection to a remote computer To establish an FTP connection to the remote computer that contains the files to be accessed: 1. At the UNIX prompt, type: ftp> remote_computer The default port for an FTP connection is 21. To specify a different port, include the port number, as follows: ftp> remote_computer port_number After a connection to the remote computer is established, a message similar to the following appears: Connected to remote_computer 220 UNIX Archive FTP server ready. 2. Log in to the DXUL-SM system. How to log in to the DXUL-SM system on page 29 provides instructions. 28 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

29 Using the File Transfer Protocol How to log in to the DXUL-SM system To log in to the DXUL-SM system: 1. Connect to the remote DXUL SM host by using the FTP and SM specific port number. 2. Log in to the DXUL-SM system the same way you log in to the local computer by providing a login name and a password: Name: bob Password: The password is not echoed to the screen: If the login is successful, an FTP prompt appears, as follows: ftp> If the login fails, FTP issues a reply. Appendix B, FTP Reply Codes, provides more information on FTP replies. 3. Type the appropriate DiskXtender FTP command. DiskXtender FTP commands on page 27 provides more information on DiskXtender FTP commands. Getting started 29

30 Using the File Transfer Protocol Retrieving files from tape Retrieving a file from tape is slower than retrieving a file from disk. While the get command is used to retrieve a file that is stored on tape, a message may appear to indicate that the file is being retrieved from the archive. Once the file is retrieved, you must type the get command a second time to obtain the file. How to use the quote wait command Unless you initially run the quote wait command, the FTP client does not wait until the file is cached from tape to disk. To cache (copy) a file from tape to disk: 1. Type the quote wait command. This command turns waiting on. The process of caching a file from tape to disk completes before returning you to the FTP prompt. 2. Type the get command. Note: By default, waiting is turned off. How to use the quote stage command To avoid issuing two get commands or waiting for the file to be cached, use the quote stage command before the file is actually needed. The quote stage command enables you move a file from tape into the disk cache before the file is actually needed. To move a file from tape into the disk cache: 1. Type the quote stage command. Once the file has been cached (staged) to disk, you need only to issue the get command once to obtain the file. 2. Type the get command. DiskXtender FTP commands on page 27 provides more information on the quote stage command. 30 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

31 Using the File Transfer Protocol How to determine whether a file is on disk or tape Use the dir command to see whether the file is currently stored on disk (DK) or on secondary storage (AR) to determine if it needs to be staged: Files on disk use DK as an identifier. Files on secondary storage, such as tape media, use AR as an identifier. The following provides output that is typically returned from the FTP dir command: ftp> dir 200 PORT command successful. 150 Opening ASCII mode data connection for /diskxtender/production/bin/dir (0 bytes). -rw u1 user AR common 4165 Feb 23 21:16 banner -rw u1 user DK common 2458 Feb 23 21:16 basename -rw u1 user AR common 721 Feb 23 21:16 batch -rw u1 user DK common 2562 Feb 23 21:16 bc 226 Transfer complete bytes received in 6 seconds (0.17 Kbytes/s) The DXUL-SM dir command in FTP provides two extra columns. Column 5 contains the identifier DK or AR, which describes the highest layer media on which the file is stored. Column 6 displays what family the file belongs to. In the output, the family is named common. The setfam command is used to assign the family name. Retrieving files from tape 31

32 Using the File Transfer Protocol Sample FTP Session The following section contains a sample FTP session that uses a subset of common FTP commands. In this sample session, the following configuration applies: The remote computer is called remote_computer. The login name is bob. 1. To begin the session, type the ftp command at the UNIX prompt: ftp> remote_computer 1021 Connected to remote_computer 200- UNIX Archive FTP Server(DiskXtender Version(2.11)) active. 200 UNIX Archive FTP server ready. This command establishes a connection to remote_computer. 2. Type the login name and password: NAME: bob 331 Password required for bob. PASSWORD: 230 User bob logged in. Note: The password is not echoed to the screen. 3. To determine the current remote directory, type: ftp> pwd 257 "/users/comp/bob" is current directory. The current remote directory is /users/comp/bob. 4. To display the contents of the /users/comp/bob directory, type: ftp> ls 200 PORT command successful. 150 Opening ASCII mode data connection.. 32 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

33 Using the File Transfer Protocol...trash file1 file2 file3 226 Transfer complete. 5. Use the bin command to set the transfer mode to binary: ftp> bin 200 Type set to I. 6. To transfer two files, file4, and file5, from the local computer to the current remote directory on remote_computer, type: ftp> mput file4 file5 mput file4? y 200 PORT command successful. 150 Opening BINARY mode data connection for file Transfer complete. local: file4 remote: file bytes sent in 0.09 seconds mput file5? y 200 PORT command successful. 150 Opening BINARY mode data connection for file Transfer complete. local: file5 remote: file bytes sent in seconds Interactive prompting is on by default. Before each file is transferred, the user must type y for yes. 7. To display the files and their attributes of the current remote directory, type: ftp> dir 200 PORT command successful. 150 Opening ASCII mode data connection for /diskxtender/production/bin/dir (0 bytes). -rw u1 user DK common 1024 Feb 10 10:76.trash -rw u1 user AR common 2458 Feb 20 15:16 file1 -rw u1 user DK common 721 Feb 20 15:16 file2 -rw u1 user AR common Feb 20 15:16 file3 -rw u1 user DK common 8445 Feb 23 16:11 file4 -rw u1 user DK common Feb 23 16:12 file5 226 Transfer complete bytes received in 6 seconds (0.17 Kbytes/s) Sample FTP Session 33

34 Using the File Transfer Protocol The output for the dir command contains two additional columns (column 5 and 6): Column 5 identifies the highest layer of the hierarchy on which each file is stored. Both file1 and file3 are not located in the disk cache. They are both stored in the archive. Column 6 displays the family name, common. The setfam command is used to assign the family name. 8. To copy file2 from the current remote directory to the local computer and rename it to newfile, type ftp> get file2 newfile 200 PORT command successful. 150 Opening BINARY mode data connection for file Transfer complete. local: newfile remote: file bytes received in.09 seconds 9. To end the FTP session, type: ftp> quit 221 Goodbye The bye command is a synonym for the quit command, and can be used interchangeably. For more information on FTP, the UNIX man pages on the local computer provides information: man ftp 34 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

35 4 Trash Can This chapter contains the following sections: Trash can description How to retrieve files Trash Can 35

36 Trash Can Trash can description The trash can is a DiskXtender safety feature that enables you to recover files deleted from DiskXtender directories. Each DiskXtender user has a directory named.trash in the home directory. When you delete a file from the DiskXtender directory structure, the file is removed from that directory and moved into the.trash directory. When this occurs, the DXUL-SM software renames the files to avoid name conflicts. Two-character strings are added as extensions to each file: The date the file was moved into.trash. A global counter that ensures that multiple files with the same name and that are deleted simultaneously from different directories are distinguishable. For example, the.trash filename given to a file originally named file1 would appear as: file1# #01:09:30pst#0064 Unlike UNIX filenames, DiskXtender filenames are not limited in length. A file remains in.trash until a predefined timeout period elapses. The initial timeout period is set by the system administrator. When the timeout period is reached, the file is automatically deleted from the.trash file. This deletion is final. Trash can limitations The following operations cannot be performed on the.trash directory. You cannot delete the.trash directory itself. You cannot move or rename the.trash directory. You cannot rename entries in.trash, because DiskXtender uses the date (first ASCII string extension) to determine when the timeout period has expired. Use the following commands with the trash can: To move files out of the trash can using FTP, use the FTP rename command. To move files out of the trash can using NFS, use the mv command. You cannot use the put (FTP), mv, or cp (NFS) commands to place files directly into the.trash directory. 36 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

37 Trash Can How to retrieve files Table 1 Two methods can be used to retrieve files from the.trash directory: Use the FTP rename or NFS mv command to move the file out of the trash can and into another directory. Give the file a different name. Use FTP or NFS commands to retrieve a file from the trash can before the timeout period expires. Table 1 on page 37 provides the trash can operation commands. Trash can operations Operation FTP commands NFS commands List the contents of.trash dir ls ls -la Retrieve files from.trash get cp mv Delete entries in.trash del rm How to retrieve files 37

38 Trash Can 38 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

39 A FTP Commands This appendix contains the following sections: UNIX commands for FTP FTP partial read DiskXtender commands for FTP FTP Commands 39

40 FTP Commands UNIX commands for FTP Table 2 on page 40 lists UNIX commands for FTP with a description, syntax, and example for each. Note: Not all systems accept these shortcut commands. These commands can be entered only at the FTP prompt. For additional standard FTP commands, the UNIX man page for FTP. provides information. Table 2 UNIX commands for FTP (page 1 of 6) Command append ascii binary bye cd Details Description: Appends a local file to a file on the remote computer. If the remote file is not specified, the local filename is used. Syntax: append local_file remote_file Example: ftp> append /usr/bob/newfile /users/comp/bob/file1 Description: Sets the file transfer type to ASCII. The ASCII transfer type is typically used when transferring ASCII files between computers which have different character sets. Do not transfer binary files while in ASCII mode. The ASCII mode performs character translations of certain characters. These characters occur randomly in a binary file and their translation may result in the corruption of the binary file. Syntax: ascii Example: ftp> ascii Description: Sets the file transfer type to support binary image transfer. Binary file transfer is faster than ASCII file transfer. Syntax: binary Example: ftp> binary Description: Terminates the FTP session with the remote server and exits FTP. Syntax: bye Example: ftp> bye Description: Changes the current directory on the remote computer to the directory specified. Syntax: cd remote_directory Example: ftp> cd /users/comp/bob 40 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

41 FTP Commands Table 2 UNIX commands for FTP (page 2 of 6) Command cdup close delete dir Details Description: Changes the current remote computer directory to its parent directory. Syntax: cdup Example: ftp> cdup Description: Terminates the FTP session with the remote server and returns to the command interpreter (FTP prompt). Once the connection is closed, use the open command to connect to another remote server. Syntax: close Example: ftp> close Description: Deletes the specified remote file from a remote directory. Syntax: delete remote_file Example: ftp> delete /users/comp/bob/file1 Description: Displays the files and their attributes in the directory on the remote computer. If the directory is not specified, the current remote directory is displayed. Syntax: dir remote_directory Example: ftp> dir /users/comp/bob UNIX commands for FTP 41

42 FTP Commands Table 2 UNIX commands for FTP (page 3 of 6) Command get hash help lcd Details Description: Copies a remote file from a remote directory to the local computer. If no pathnames are specified, the DXUL-SM software copies the remote file from the current remote directory to the current local computer directory. Syntax: get remote_file local_file Example: ftp> get /users/comp/bob/file1 /usr/bob/newfile Copies /users/comp/bob/file1 from the remote computer to /usr/bob/newfile on the local computer. ftp> get file1 newfile Copies file1 from the current remote directory to newfile in the current local computer directory. ftp> get file1 /usr/bob/newfile Copies file1 from the current remote directory to /usr/bob/newfile on the local computer. ftp> get /users/comp/bob/file1 If the directory /users/comp/bob exists, /users/comp/bob/file1 is copied from the remote computer to /users/comp/bob/file1 on the local computer. If /users/comp/bob does not exist on the local computer, this command returns an error. Description: Toggles the printing of the pound sign (#) on the screen for each data block transferred. The size of the data block is computer-dependent. Syntax: hash Example: ftp> hash Description: Displays information about FTP commands. Syntax: help help command_name Example: ftp> help ftp> help get Description: Changes the current directory on the local computer. If no directory is specified, FTP changes to the local home directory. Syntax: lcd local_directory Example: ftp> lcd /usr/bob 42 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

43 FTP Commands Table 2 UNIX commands for FTP (page 4 of 6) Command ls mdelete mget mkdir mput open Details Description: Lists filenames in a remote directory. If the remote directory is not specified, FTP lists the current remote directory. Syntax: ls remote_directory Example: ftp> ls /users/comp/bob Description: Deletes multiple files. If full pathnames are not specified, the default is the current remote directory. Wildcard characters (*,?, [ ]) may be used. Syntax: mdelete remote_file1 remote_file2... Example: ftp> mdelete file1 file2 The file1 and file2 files are deleted from the current remote directory. ftp> mdelete /users/comp/bob/file1 /users/comp/barb/file1 The /users/comp/bob/file1 and /users/comp/barb/file1 files are deleted. Description: Gets multiple files. This command retrieves specified files from one or more remote directories, and transfer them to the current local directory. Wildcard characters include *,?, [ ]. Syntax: mget remote_file1 remote_file2... Example: ftp> mget file1 file2 ftp> mget /users/comp/bob/file1 /users/comp/barb/file1 Description: Makes a directory on the remote computer. If no pathname is specified, the directory is inserted into the current remote directory. Syntax: mkdir remote_directory Example: ftp> mkdir /users/comp/bob/dir2 Description: Transfers multiple local files from one or more local directories to the current remote directory. Wildcard characters include *,?, [ ]. Syntax: mput local_file1 local_file2 local_file3... Example: ftp> mput file1 file2 file3 ftp> muput /usr/bob/file1 /usr/barb/file1 Description: Establishes a connection to the specified host (remote) FTP server. If an optional port number is specified, FTP attempts to contact an FTP server at that port. Syntax: open host [port] Example: ftp> open remote_computer ftp> open remote_computer 1012 UNIX commands for FTP 43

44 FTP Commands Table 2 UNIX commands for FTP (page 5 of 6) Command prompt put pwd quit quote Details Description: Toggles interactive prompting. If prompting is enabled, the user must respond with a Y or N to each file specified by an mget or mput command. If prompting is disabled, an mget or mput command transfers all files specified. The default prompt value is set to on. Syntax: prompt Example: ftp> prompt Description: Copies a local file from a local directory to a remote computer. If no pathnames are specified, the DXUL-SM software copies the local file from the current local directory to the current remote computer directory. Syntax: put local_file remote_file Example: ftp> put /usr/bob/file1 /users/comp/bob/newfile: Copies /usr/bob/file1 from the local computer to /users/comp/bob/newfile on the remote computer. ftp> put file1 newfile: Copies file1 from the current local directory to newfile in the current directory on the remote computer. ftp> put file1 /users/comp/bob/newfile: Copies file1 from the current local directory to /users/comp/bob/newfile on the remote computer. ftp> put /usr/bob/file1: If the directory /usr/bob exists on the remote computer, /usr/bob/file1 is copied from the local computer to /usr/bob/file1 on the remote computer. Description: Displays the name of the current remote directory. Syntax: pwd Example: ftp> pwd Description: Terminates the FTP session with the remote server and exits FTP. The quit command is synonymous with the bye command. Syntax: quit Example: ftp> quit Description: Sends the specified arguments or commands to the remote FTP server. Syntax: quote arg1 arg2... Example: ftp> quote stage 60 /users/comp/bob/newfile 44 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

45 FTP Commands Table 2 UNIX commands for FTP (page 6 of 6) Command recv rename reset rmdir send status user Details Description: Can be used instead of the get command. Syntax: recv remote_file [local_file] Example: See the get command. Description: Renames a file on the remote computer. Syntax: rename old_name new_name Example: ftp> rename /users/comp/bob/oldfile /users/comp/bob/newfile Description: Clears the reply queue, and re-synchronizes command and reply sequencing with the remote FTP server. Syntax: reset Example: ftp> reset Description: Deletes a directory on the remote computer. If no pathname is specified, the rmdir command deletes the directory from the current remote directory. Syntax: rmdir remote_directory Example: ftp> rmdir /users/comp/bob Description: Can be used instead of the put command. Syntax: send local_file remote_file Example: See the put command. Description: Displays the current status of FTP. Syntax: status Example: ftp> status Description: Identifies you as the same or different user, to the remote FTP server. If you type only the login name, you are prompted for a password (and account, if required). The password is not echoed to the screen.the login name and password are entered all on one line. Syntax: user login_name [password] [account] Example: ftp> user bob ftp> user bob XXXX UNIX commands for FTP 45

46 FTP Commands FTP partial read The DXUL-SM software expands on FTP features through the use of the quote command called offlen. To read files partially, execute the offlen command followed by a get request. ftp> quote offlen <file offset> <length in bytes> <filename> 46 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

47 FTP Commands DiskXtender commands for FTP Table 3 on page 47 contains DiskXtender commands for FTP, and a description, syntax, and example for each. Table 3 DiskXtender commands for FTP (page 1 of 7) Command allo pallo chgrp Details Description: Specifies the size (in bytes) of the next file to be transferred by the put command, and applies only to the next time you use the put command. Use this command to improve the efficiency of binary transfers. Some FTP clients automatically use the allo command. Syntax: quote allo filesize Example: ftp> quote allo Description: Sets the space allocation (in bytes) for each transfer for the remainder of the FTP session (or until pallo is entered again). Syntax: quote pallo filesize Example: ftp> quote pallo Description: Changes the group associated with a remote file. To use the chgrp command, you must be the owner of the file and a member of the new group (or the superuser). Syntax: quote chgrp group_name filename Example: ftp> quote chgrp group1 file1 mchgrp Description: Changes the group for multiple files. Syntax: quote mchgrp group_path where group_path is a filepath ending in a wildcard expression, for example: /usr/local/tmp/* Example: ftp> quote mchgrp DiskXtender commands for FTP 47

48 FTP Commands Table 3 DiskXtender commands for FTP (page 2 of 7) Command chmod mchmod chown mchown direct gtrsh (get trash) Details Description: Changes permissions on a remote file. The permissions must be in octal notation. For more information on octal permission notation, the UNIX man page for chmod provides information. To use the chmod command, you must be the owner of the file or the superuser. Symbolic chmod parameters are not supported with the FTP chmod command. Syntax: quote chmod permissions filename Example: ftp> quote chmod 700 /users/comp/bob/file1 Description: Changes the permissions on remote files. To use the mchmod command, you must be the owner of the file and in the new group or the superuser. Syntax: quote mchmod permissions path Example: ftp> quote mchmod 777 * Description: Changes the owner of a remote file. To use the chown command, you must be the superuser. Syntax: quote chown owner_name filename Example: ftp> quote chown bob file1 Description: The mchown command is used to change the owner of remote files. To use the mchown command, you must be the superuser. Syntax: quote mchown owner_name filenames Example: ftp> quote mchown nobody * Description: Enables or disables direct mode. The default value is set to off. When direct mode is enabled, files are retrieved directly from the storage media by passing the disk cache. This command is best used if the file that is retrieved will not be read again and it is relatively large. Syntax: quote direct Example: ftp> quote direct Description: Displays the current DiskXtender trash can timeout interval. The timeout interval is displayed in minutes. Chapter 4, Trash Can, provides more information. Syntax: quote gtrsh Example: ftp> quote gtrsh 48 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide

49 FTP Commands Table 3 DiskXtender commands for FTP (page 3 of 7) Command strsh (set trash) ln nmdup Details Description: Changes the DiskXtender trash can timeout interval. Once the timeout is changed, it remains at this value after the FTP session is terminated. The timeout is specified in minutes. Chapter 4, Trash Can, provides more information. Syntax: quote strsh time Example: ftp> quote strsh 60 Description: Creates a symbolic link. Syntax: quote ln file1 file2 where: file1 is the existing file or directory to be linked. file2 file is the symbolic link. Example: ftp> quote ln /usr/diskxtender /usr/bob/ut Description: Enables you to view or set a numeric value for duplicate copies. The numeric value determines how many duplicates of DiskXtender files are copied to tape. After setting the number of duplicate copies, each file that is copied to the DiskXtender file system is also duplicated (copied) n number of times to n number of tapes. This duplicate copy setting is temporary and returns to the default value when you end the FTP session. The maximum number of copies, which is set by the system administrator, is restricted to 15 or less. Syntax: quote nmdup [n] where n is the number of duplicate copies. Example: ftp> quote nmdup Returns the current numeric setting for duplicate copies. ftp> quote nmdup 5 Sets the number of duplicate copies to 5. DiskXtender commands for FTP 49

50 FTP Commands Table 3 DiskXtender commands for FTP (page 4 of 7) Command purge purgetype Details Description: Enables you to specify a file that can be removed from the disk cache when space is needed. Use the purge command on a file that is not likely to be accessed in the near future. The purge command, in addition to the DXUL-SM software, helps maintain space in the disk cache for files that are frequently accessed. Syntax: quote purge [type] file where type is one of the following: reset (default) priority immediate never The type variable is optional. If type is not specified, the session value for type is used. If type is specified, you can override the session value on a file-by-file basis. Example: ftp> quote purge never /users/comp/bob/file1 Description: Sets the default purge type for the session to a priority of type. DXUL-SM permits setting a file characteristic that determines when (and if) a file is purged from the cache. The purge types define this quality. The purgetype command lets you set this characteristic for all files that are accessed in the current FTP session. Syntax: quote purgetype [type] where type is one of the following: reset (default) priority immediate never last If a type is not specified, the current value for type is displayed. Example:ftp> quote purgetype immediate Files in the DXUL-SM cache are immediately available for purging. 50 EMC DiskXtender for UNIX/Linux Storage Manager Release 2.11 User Guide