| <:=--=:><:=--=:><:=--=:><:=--=:>\|/<:=--=:><:=--=:><:=--=:><:=--=:> |
| <:=--=:> <:=--=:> |
| <:=--=:> >>>>>=-* Users Guide to VAX/VMS *-=<<<<< <:=--=:> |
| <:=--=:> <:=--=:> |
| <:=--=:> Part II of III <:=--=:> |
| <:=--=:> <:=--=:> |
| <:=--=:> Part C: Using the Utilities <:=--=:> |
| <:=--=:> Part D: Advanced Guide to VAX/VMS <:=--=:> |
| <:=--=:> <:=--=:> |
| <:=--=:> By Black Kat <:=--=:> |
| <:=--=:> <:=--=:> |
| <:=--=:><:=--=:><:=--=:><:=--=:>/|\<:=--=:><:=--=:><:=--=:><:=--=:> |
|
|
| Index |
| ~~~~~ |
| Part C contains information on the following topics: |
|
|
| o Help Utility o Phone Utility |
| o Backup Utility o Library Utility |
| o Mail Utility o Sort Utility |
|
|
| Part D contains information on the following topics: |
|
|
| o Subprocesses o DECnet |
| o Attaching to a Process o Proxy Access |
| o Interrupting a Process o Task-to-Task Communication |
| o Batch Processing o Remote Printing |
| o Controlling Batch Jobs o VAXclusters |
|
|
| <:=- Part C : Using the Utilities -=:> |
|
|
| Help Utility |
| ~~~~~~~~~~~~ |
| The VAX/VMS Help Utility is almost like having a DCL dictionary online. It |
| includes an explanation of each DCL command and can optionally explain valid |
| command parameters. Help also provides information about other VAX/VMS |
| utilities and system services. |
|
|
| There are two modes available for the help utility. If you know the DCL |
| command, utility or system service you want more information about, use direct |
| mode. If you don't know the command, use query mode. Query mode can also be |
| used to see which other commands and other subjects are referenced by the help |
| utility. |
|
|
| To use query mode, just type HELP <enter> at the DCL command level. Help will |
| display an alphabetical listing of all DCL commands and other topics for which |
| information is available and you will be prompted with: "Topic?" |
|
|
| You can exit Help by pressing <enter> or <Ctrl-C> or <Ctrl-Z> or get |
| information by typing in the command or subject name followed by <enter>. When |
| you request information on a command, Help will display details including how |
| the command is invoked, what it does and the default values. Most topics will |
| have subtopics available which will be listed alphabetically followed by the |
| prompt: "COMMAND-NAME Subtopic?" |
|
|
| You can select subtopic help or press <enter> to return to the "Topic?" prompt. |
| If you want to see all the information available on a command, type in "HELP |
| command_name ..." or "HELP command_name *". |
|
|
| To use direct mode, enter HELP topic_name <enter>. This will bypass the |
| listing of available topic. Additionally, you can enter a valid DCL command |
| with or without qualifiers in this mode. For example, to get information on |
| the DCL SET command /TERMINAL qualifier, you could enter $ HELP SET TERMINAL. |
| The help utility will provide information on the SET/TERMINAL command and |
| prompt you for another subtopic since information on other qualifiers is |
| available. |
|
|
| For more information and details on the help utility, you can use: |
| $ HELP HINTS or $ HELP HELP/INSTRUCTIONS. |
|
|
|
|
| Backup Utility |
| ~~~~~~~~~~~~~~ |
| The backup utility is usually used by system managers to back up system disks, |
| insuring a recent copy of data should the system disks become unreliable. |
| Generally, the system disks are backed up to magnetic tape or removable disk |
| packs, which are then removed and stored in a save location offline. Users may |
| use the backup utility on files in their own accounts to make copies for safe |
| keeping, transferring to another system, or for offline storage. |
|
|
| To use the backup utility, you have to decide what you want to back up, and how |
| you want it done. You have the following options: |
|
|
| Selective : Files are backed up according to a specified criteria. |
| Qualifiers (e.g. /DATE) and file specifications (e.g. *.TXT) |
| are used for specifying these criteria. |
| File by File: Individual files or entire file directories are backed up. |
| Directories are created when copying, unlike the copy command. |
| Incremental : Saves file created since the most recent backup. Usually |
| performed by system operators. |
| Physical : An exact duplicate of a volume is saved. All file structures |
| are ignored and the copy is a bit-by-bit duplicate. |
| Image : A functionally equivalent copy of the original volume is |
| created. Typically done on bootable volumes and system disks. |
|
|
|
|
| To back up files to a subdirectory: $ BACKUP F1.TXT,F2.TXT,*.DAT [BY.JUNK] |
|
|
| To copy a directory tree: $ BACKUP [dir...]file_spec [dir...]file_spec |
|
|
| To copy disk volumes: $ MOUNT/FOREIGN DJA1: |
| $ BACKUP/IMAGE DUA2: DUA1: |
|
|
| To copy to tape: $ INITIALIXE MUA0: TAPE (the first time its used) |
| $ MOUNT/FOREIGH MUA0: |
| MOUNT-I-MOUNTED, TAPE mounted on __MUA0: |
| $ BACKUP [.DRV]MV_DYDRV.MAR MUA0:[]MV_DYDRV.MAR |
|
|
| A save set is a single file containing multiple files that have been backed up. |
| To make a save set: |
|
|
| $ MOUNT/FOREIGN MUA0: |
| MOUNT-I-MOUNTED, TAPE mounted on __MUA0: |
| $ BACKUP DUB1:[BY.JUNK]*.*;* MUA0:08JUN.BAK/SAVE_SET |
|
|
| A single file can be retrieved from a save set by using the /SELECT qualifier. |
| For example, to restore the file LOGIN.COM from the previously backed up save |
| set: |
|
|
| $ MOUNT/FOREIGH MUA0: |
| MOUNT-I-MOUNTED, TAPE mounted on __MUA0: |
| $ BACKUP |
| __From: MUA0:08:JUN.BAK/SAVE_SET/SELECT=[BY.JUNK]LOGIN.COM |
| __To: *.* |
|
|
| Listing a save set: $ MOUNT/FOREIGN MUA0: |
| MOUNT-I-MOUNTED, TAPE mounted on __MUA0: |
| $ BACKUP/LIST MUA0:08JUN.BAK/SAVE_SET |
|
|
| Selective backups: $ BACKUP *.*/SINCE=12-APR-1988 MUA0:08JUN.BAK/SAVE_SET |
| $ BACKUP |
| __From: *.*/SINCE=12-APR-1988/EXCLUDE=[*.TMP,*.LOG] |
| __To: MUA0:08JUN.BAK/SAVE_SET |
|
|
|
|
| The following is a list of some other qualifiers you'll find useful. |
|
|
| Qualifier Function |
| ~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| /LOG Writes log message to terminal as each backup file is written. |
| /VERIFY Verifies the copy or save set with the original after copy. |
| /CONFIRM Display each filename and ask for confirmation before copy. |
| /DELETE Deletes source file after destination file written. |
|
|
|
|
| Mail Utility |
| ~~~~~~~~~~~~ |
| When you receive new mail, a message will be sent to your terminal unless the |
| /NOBROATCAST qualifier has been specified with the SET TERMINAL command. Mail |
| is an interactive utility that understands many commands in a format identical |
| to DCL commands. The utility is invoked by typing "$ MAIL" at the DCL command |
| level. Mail has a built in help feature which works the same way as the |
| VAX/VMS Help Utility. Mail may be sent interactively or directly. |
|
|
| Interactive implies the use of the mail utility in conversational mode by |
| invoking mail at the DCL command level. After invoking the mail utility, use |
| the SEND command, and mail will prompt you for the name of the user(s) you want |
| to send the mail to, your name, the subject, and the message text which you |
| will terminate with <Ctrl-Z>. When you press <Ctrl-Z> the message is sent and |
| you are returned to the mail prompt where you can type EXIT to quit. |
|
|
| To send mail in direct mode from the DCL command line, use the following |
| format: $ MAIL file_spec user /SUBJECT="character string" where "file_spec" |
| is a valid VAX/VMS file specification containing the body of your mail message |
| and "user" is the name of a user on your local system or remote node. The |
| /SUBJECT qualifier is optional. |
|
|
| To send mail to multiple users (like a mailing list) create a file with a list |
| of the account names of every user you want to receive the message. Then enter |
| @FILENAME at the "To:" prompt and each user listed in the distribution list |
| will receive a copy of your mail. A distribution list may also contain another |
| distribution list by preceeding the second name with an at sign (@). Comments |
| are included by using an exclamation point (!). The following is a sample |
| distribution list: |
|
|
| ! VAX.DIS |
| ! |
| ! Staff |
| JONES |
| OPER |
| BYNON |
| ! |
| ! Accounting personnel |
| @ACTLIST |
|
|
| To read your mail, just type MAIL <enter> and you will be told how many |
| messages you have waiting. Read is the default command, so you can just |
| press <enter> to start reading them. To reply to a message, use the REPLY or |
| ANSWER commands and the mail utility will fill out the header information |
| automatically. You can store your mail in folders for later reference. The |
| system has three default folders (MAIL, NEWMAIL, and WASTEBASKET). |
|
|
| MAIL is the default mail folder and always exists. It is used to store mail |
| messages after you've read them unless you file these messages in other folders |
| you've created. |
|
|
| The NEWMAIL folder stores mail messages before you read them, like a mailbox. |
| They're automatically moved to the MAIL folder after you've read them unless |
| you specify a different destination folder with the MOVE command. |
|
|
| The WASTEBASKET folder is a temporary folder used to store messages that have |
| been deleted. These messages remain in the WASTEBASKET folder until you exit |
| the mail utility, at which time they're thrown out permanently. |
|
|
| To create new folders, select a message and enter the MOVE command. If you |
| attempt to move a message to a nonexistent folder, you'll be asked if you want |
| to create a new folder. For example: |
|
|
| MAIL> 11 |
| MAIL> MOVE MEMOS |
| Folder MEMOS does not exist. Create it (Y/N, default is N)? Y |
| MAIL-NEWFOLDER, folder MEMOS created MAIL> |
|
|
| The SELECT command allows you to move from one folder to another. For example, |
| if you type SELECT JUNK at the "MAIL>" prompt, you will be moved to the JUNK |
| folder, and mail will respond with the number of messages contained in the new |
| folder. |
|
|
| The DELETE command accepts a message number as a parameter or deletes the |
| current message if a message number is not supplied. To delete a folder, just |
| delete all the messages in that folder with the DELETE qualifier /ALL. |
|
|
| To log a mail message to a file, use the EXTRACT qualifier. If the /NOHEADER |
| qualifier is used, the header information will not be included. For example: |
| EXTRACT/NOHEADER MEMO.TXT will save the currently selected message to a file |
| named MEMO.TXT. |
|
|
| For more information on the mail utility, use mail's HELP command. |
|
|
|
|
| Phone Utility |
| ~~~~~~~~~~~~~ |
| The VAX/VMS Phone Utility allows you to talk to other users on your system. It |
| simulates a real telephone with such features as call holding, conference calls |
| and telephone directories. The Phone utility only works with VT100, VT200 or |
| compatible terminals. |
|
|
| To call someone with the phone utility, enter "$ PHONE username" where username |
| is the person you want to talk to. Your screen will split horizontally in half |
| and indicate that the phone utility is ringing the other person. Your half of |
| the conversation will be displayed on the top of the screen and the other |
| person's will appear on the lower half. |
|
|
| The phone utility may also be used interactively by entering "$ PHONE", and you |
| will now be given the phone prompt (%). You can enter commands directly now |
| (e.g. "% DIRECTORY"). The phone utility has an online help facility just like |
| the mail utility. |
|
|
|
|
| Library Utility |
| ~~~~~~~~~~~~~~~ |
| Sometimes its easier to maintain a single file instead of a group of related |
| files. The VAX/VMS Library Utility lets you create and maintain a specially |
| formatted file called a library in which you can store groups of single files |
| called modules. Predefined libraries include text, help, object, sharable |
| image and macro. Many VAX/VMS utilities such as HELP and LINK are capable of |
| processing library files. Unless you're a programmer or system manager, |
| you'll probably only use text and help libraries. |
|
|
| To create a library use the LIBRARY command's /type qualifier and the /CREATE |
| qualifier. The /type qualifiers are: /TEXT, /SHARE, /HELP, /OBJECT, /MACRO. |
| For example to create a text library named BOOK.TLB: |
|
|
| $ LIBRARY/TEXT/CREATE BOOK. |
|
|
| You may optionally specify a list of files to be included in a library when it |
| is created. For example: |
|
|
| $ LIBRARY/TEXT/CREATE BOOK TOC,C1,C2,INDEX |
|
|
| To list the names of modules in a library, use the /LIST qualifier: |
|
|
| $ LIBRARY/TEXT/LIST BOOK |
| Directory of TEXT library BOOK.TLB;1 on 12-JUN-1989 14:12:07 |
| TOC |
| C1 |
| C2 |
| INDEX |
|
|
| You can also display a history of updates made to the library by using the |
| /HISTORY qualifier with the /LIST qualifier. |
|
|
| To add modules to an existing library, use the /INSERT qualifier: |
|
|
| $ LIBRARY/TEXT/INSERT BOOK CH3 |
|
|
| To update a module in a library, do the following: |
|
|
| o Extract the module to be updated with the /EXTRACT qualifier. |
| o Make the necessary changes. |
| o Write over the old module with the /REPLACE qualifier. |
|
|
| For example: $ LIBRARY/TEXT/EXTRACT BOOK CH2 |
| $ EDIT CHAP2.TXT |
| . |
| . (edit the file) |
| . |
| $ LIBRARY/TEXT/REPLACE BOOK CH2 |
|
|
|
|
| Sort Utility |
| ~~~~~~~~~~~~ |
| The VAX/VMS Sort Utility will reorganize records within a file. The simplest |
| form of the sort command will organize records in ascending alphabetical order. |
| For example, to sort BOOK.TXT, you could issue the command: |
|
|
| $ SORT BOOK.TXT SORTED.TXT |
|
|
| The Sort utility sorts on the first character of the field in each record in |
| the input file. If there is more than one field or column in a record, the |
| entire record is ordered, not just the first field. |
|
|
| Here's an example of sorting in descending order numerically with multiple |
| fields. The sample data file JUNK.TXT contains two fields of data. The first |
| field contains a name, and the second field, starting in column 9 contains the |
| two-digit number we're sorting by: |
|
|
| PAT 47 |
| PAT 47 |
| JIM 09 |
| TOM 23 |
| RICH 43 |
| GARY 02 |
| KURT 13 |
| KEVIN 27 |
|
|
| Sort the file: $ SORT/KEY=(POSITION=9,SIZE=2,DESCENDING) JUNK.TXT SORTED.TXT |
|
|
| The sorted file (SORTED.TXT) will now look like this: |
|
|
| PAT 47 |
| RICH 43 |
| KEVIN 27 |
| TOM 23 |
| KURT 13 |
| JIM 09 |
| GARY 02 |
|
|
|
|
| <:=- Part D : Advanced Guide to VAX/VMS -=:> |
|
|
| Subprocesses |
| ~~~~~~~~~~~~ |
| A major benefit of the VAX/VMS operating system is its support of multi- |
| processing. This is not restricted to multiple users logged into different |
| terminals however. VAX/VMS users may create multiple processes known as |
| subprocesses from within their main processes. |
|
|
| The DCL SPAWN command is used to create a subprocess. The SPAWN command will |
| create a subprocess with the attributes (default directory, privileges, memory, |
| etc.) of its parent process unless otherwise specified. For example: |
|
|
| $ SPAWN |
| % DCL-S-SPAWNED, process BYNON_1 spawned |
| % DCL-S-ATTACHED, terminal now attached to process BYNON_1 |
|
|
| In this case, the parent process is put into hibernation, the subprocess is |
| given control of the keyboard, and we are left at the DCL prompt. You can now |
| enter any DCL commands, utilities, or other programs. To return to the parent |
| process, just $ LOGOUT of the subprocess: |
|
|
| $ LOGOUT |
| Process BYNON_1 logged out at 12-JUL-1981 13:04:17.10 |
| $ DCL-S-RETURNED, control returned to process BYNON |
|
|
| The SPAWN qualifier /NOLOG can be used to suppress the informational messages |
| generated when a subprocess is created or logged out. DCL Commands, procedures |
| and VAX/VMS images (utilities and programs) may be executed directly with SPAWN |
| by entering the correct syntax for the command or procedure after the SPAWN |
| command. For example: $ SPAWN/NOLOG MAIL |
|
|
| If you have a task that can execute without user intervention (e.g. a program |
| compiler), you can spawn a task to run as a background process to your current |
| process. For example: $ SPAWN/NOWAIT FORTRAN VAXBBS |
|
|
| The SPAWN qualifier /NOWAIT spawns the task to run concurrently (parallel) to |
| the parent process. Both processes will share the terminal and any messages |
| >from the background task will be displayed at the terminal. To avoid possible |
| conflicts, use the /OUTPUT qualifier: |
|
|
| $ SPAWN/NOWAIT/OUTPUT=COMPILE.LOG FORTRAN.VAXBBS |
|
|
| When the job in the subprocess is complete it will terminate and be removed |
| >from the system. |
|
|
|
|
| ATTACHing to a Process |
| ~~~~~~~~~~~~~~~~~~~~~~ |
| You can use the DCL ATTACH command to connect your keyboard to any process or |
| subprocess you've created. To exit from BYNON_1 back to BYNON with the ATTACH |
| command, enter "$ ATTACH BYNON" and the subprocess hibernates while you are |
| returned to the parent process. |
|
|
|
|
| Interrupting a Process |
| ~~~~~~~~~~~~~~~~~~~~~~ |
| You can interrupt a process at anytime to create a subprocess by pressing |
| <Ctrl-Y> and then using the SPAWN command. When you're done working with the |
| subprocess and have returned to the interrupted process, type CONTINUE to start |
| processing again where you left off. Some VAX/VMS utilities, such as MAIL, |
| support SPAWN intrinsically, so you can spawn a process within these utilities |
| by entering the SPAWN command without pressing <Ctrl-Y> first. |
|
|
|
|
| Batch Processing |
| ~~~~~~~~~~~~~~~~ |
| The SUBMIT command was briefly discussed in Part II: Programming the VAX. A |
| batch job is one or more DCL command procedures that execute from a detached |
| process with your privileges and quotas. The controller of the process is the |
| batch queue which accepts jobs via the SUBMIT command. Batch jobs execute |
| without user interaction, permitting you to use your terminal for interactive |
| work while the system executes the batch job (command procedure). Batch jobs |
| are used to execute tasks that take a long time to run, use many system |
| resources, or need to be scheduled to execute at a specific time. |
|
|
| The SUBMIT command will enter a command procedure to the default batch queue |
| (SYS$BATCH) if a specific queue is not provided. A command procedure submitted |
| for batch execution is given a job name which defaults to the command procedure |
| name unless otherwise specified. The entry number given to the job is used to |
| control it (delete, rename, etc.) |
|
|
|
|
| Controlling Batch Jobs |
| ~~~~~~~~~~~~~~~~~~~~~~ |
| You can specify a name for a batch job with the /NAME qualifier: |
|
|
| $ SUBMIT BACKUP /NAME=DAILY_BACK |
|
|
| You may also execute more than one command procedure by separating the |
| procedure names with a comma: |
|
|
| $ SUMBIT SORT_DATA,REPORT /NAME=WEEKLY_REPORT |
|
|
| To schedule a batch job to execute after a specific time: |
|
|
| $ SUMBIT CLEANUP /AFTER=11:40 |
| Job CLEANUP (queue SYS$BATCH, entry 39) holding until 1-JUN-1989 11:40 |
|
|
| To hold a job in the queue to be released later: |
|
|
| $ SUMBIT REMINDER /HOLD |
| Job REMINDER (queue SYS$BATCH, entry 12) holding |
| $ |
| $ SET QUEUE/ENTRY=32/RELEASE SYS$BATCH |
|
|
| To submit a job to a different queue: $ SUBMIT TESTJOB /QUEUE=SLOW |
|
|
| To lower the priority (e.g. if it's CPU intensive): |
|
|
| $ SUBMIT CRUNCH /PRIORITY=2 |
|
|
| To pass parameters: $ SUBMIT COMPILE / PARAMETERS=(WINDOWS,MISC,DISP_IO) |
|
|
| To disable the automatic printing of the batch job's log (file instead): |
|
|
| $ SUBMIT GOJOB /NOPRINT /LOG_FILE=DUA2:[BYNON] |
|
|
| This will create a file DUA2:[BYNON]GOJOB.LOG. If the /NOPRINT qualifier is |
| not specified, the log file will be printed and deleted. To print and keep the |
| log file, use the /KEEP qualifier with the /LOG_FILE qualifier. |
|
|
| After you submit a procedure to a batch queue, you can monitor its status and |
| job characteristics by using the SHOW QUEUE command. This will display the |
| name, entry number and status of all the jobs you have in queue. The /ALL |
| qualifier will display all jobs you have enough privilege to see, and the /FULL |
| qualifier provides more information about jobs, such as operating |
| characteristics and submission time. |
|
|
| You can use the SET QUEUE/ENTRY command to modify a job's priority |
| (/PRIORITY), name (/NAME), or status (/RELEASE or /AFTER). For example: |
|
|
| $ SET QUEUE /ENTRY=217 /PRIORITY=2 SYS$BATCH |
|
|
| Use the DELETE /ENTRY command to delete jobs: $ DELETE /ENTRY=18 SYS$BATCH |
|
|
|
|
| Using DECnet |
| ~~~~~~~~~~~~ |
| DECnet uses the standard VAX/VMS file specifications for remote file access. |
| In addition to a node specification, you may also include access control |
| information (username and password) in quotes. For example: |
|
|
| BURG"JONES MYPW"::DUA2:JUNK.TXT |
| | | | | | |
| | | | | +---- Filename.Extension |
| | | | | |
| | | | +---------- Device name |
| | | | |
| | | +------------------ Password |
| | | |
| | +----------------------- Username |
| | |
| +----------------------------- Node name |
|
|
| Unless a specific DECnet account exists on the host node, or proxy exists, you |
| must supply access control information to execute a command on a remote system. |
| (e.g. $ TYPE BURG""JONES MYPW"::DUA2:JUNK.TXT) |
|
|
|
|
| Proxy Access |
| ~~~~~~~~~~~~ |
| Because including access control information in a command string is a security |
| risk, Digital provides proxy access, which works by keeping a database of users |
| and hosts who may gain access to the system via DECnet. The format of the |
| database is: SYSTEM::REMOTE_USERNAME LOCAL_USERNAME. |
|
|
|
|
| Task-to-Task Communication |
| ~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| This is a feature of DECnet which allows programs on one system to communicate |
| with programs on another (e.g. the DCL TYPE command) To execute a procedure on |
| a remote system, use the TYPE command with the TASK=xxx parameter. For |
| example: |
|
|
| $ TYPE VAX1::"TASK=SHOW_USERS" |
|
|
| To show the users on a remote system you would write a command procedure |
| something like this: |
|
|
| $! Show_Users.Com |
| $! |
| $ IF FMODE() .EQS. "NETWORK" THEN GOTO NETWORK |
| $ SHOW USERS |
| $ EXIT |
| $ NETWORK: |
| $ DEFINE/USER_MODE SYS$OUTPUT SYS$NET |
| $ SHOW USERS |
| $ EXIT |
|
|
| Since SYS$OUTPUT is redirected to SYS$NET, the output is redirected to your |
| terminal over DECnet. Task-to-Task communication can be simple (like |
| Show_Users) or complicated (like programs passing data back and forth). |
|
|
|
|
| Remote Printing |
| ~~~~~~~~~~~~~~~ |
| If your DECnet network contains a LAN such as Ethernet, you'll probably have to |
| share printers with other nodes on the network. The easiest way to print a |
| file is to copy it directly to the print device. This works fine as long as |
| the device is spooled and set up with world write privileges. For example: $ |
| COPY JUNK.TXT BURG::LCA0: will copy the file JUNK.TXT to the device LCA0: on |
| node BURG. |
|
|
| Another way to print is to use the DCL PRINT/REMOTE command. However, the file |
| must be located on the remote system to use this, which is inconvenient if the |
| file you're printing is on the local system. You can still do it though: |
|
|
| $ COPY JUNK.TXT BURG::[BYNON] |
| $ PRINT /REMOTE BURG::[BYNON]JUNK.TXT |
| Job JUNK (queue SYS$PRINT, entry 512) started on LCA0 |
| $ DELETE BURG::[BYNON]JUNK.TXT |
|
|
| VAXclusters |
| ~~~~~~~~~~~ |
| The main purpose of a VAXcluster is high processor ability, shared resources, |
| and a single security and management area. There are two basic type of |
| VAXclusters, heterogeneous and homogeneous, but a mix of the two is possible. |
| The main difference between these types is how they share resources, |
| specifically the VAX/VMS OS environment. |
|
|
| The VAX/VMS OS environment is identical on each cluster in a homogeneous |
| VAXcluster. This is done by using a common system disk for all the nodes. |
| User accounts, system files, queues and storage devices are shared, and all of |
| the computers behave the same way. |
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| In a heterogeneous VAXcluster, the environment on each system is different. |
| Each VAX has its own system disk, user accounts and system files. Queues and |
| storage devices may or may not be shared. Users can work in different |
| operating environments, depending on the system they're using. |
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| Usually a VAXcluster is accessed by an Ethernet-based terminal server. Using |
| a terminal server, a user can establish a session with any VAXcluster member, |
| and the connection is identical to that of a directly connected terminal. |
| However, terminal sessions can support multiple simultaneous sessions to |
| different nodes. In the unlikely event that a VAXcluster is set up with |
| directly connected terminals and you need to access a different system, you |
| can DECnet via the SET HOST facility. All VAXcluster systems support DECnet |
| within the cluster. |
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| VAXcluster members (nodes) often share processing resources through the use |
| of print and batch queues known as cluster-wide queues, which are used the |
| same as a normal queue. The only extra information you need is the queue |
| name. A list of all the queues in a cluster can be called up with the DCL |
| SHOW QUEUE command. If you submit a job to a cluster-wide queue, you must |
| insure that the node on which it resides has access to the file you want to |
| print or the command procedure you want processed. |
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