Guardian User's Guide

Using Labeled Tapes
Guardian User’s Guide—425266-001
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Handling Labeled Tape Messages and Requests
3. Check to make sure that $TAPE1 is actually up:
> SCF STATUS TAPE $TAPE1, DETAIL
Handling Labeled Tape Messages and Requests
System operators must monitor for labeled-tape messages so they will know when errors
occur or requests for tape handling are sent. Labeled-tape requests are sent to operators
asking them to perform various tasks such as mounting or taking down a labeled-tape.
Monitoring Labeled-Tape Messages
All messages generated by labeled-tape operations are displayed at the operator console
and any other enabled terminal. These messages are generated either from the tape
processes or from the $ZSVR (labeled-tape server process) process.
$ZSVR is the central control process for all tape processes that support labeled tapes in
the system. Every tape drive in the system has a tape process associated with it. $ZSVR
monitors the status of each tape drive—whether it is free or in use, whether a tape is
currently mounted, and what the volume serial number is (if a standard labeled tape is
mounted). $ZSVR acts as the message interface between all tape processes and the
operator console. When a job wants to open a standard labeled tape or a tape drive,
$ZSVR sends the request to the operator console. $ZSVR also sends error messages and
status messages to the operator console.
Tape processes read the labels on mounted tapes and send the information to $ZSVR.
Tape processes also perform the actual reading and writing of tapes. If a tape process
encounters any problems while reading the label information on a mounted tape, it sends
an error message or warning message to the operator console.
Directing Labeled-Tape Messages to a Second Console
You can direct all labeled-tape processing messages to a second console in addition to
the operator console by using the MEDIACOM ALTER CONSOLE command. This lets
you separate labeled-tape messages from other console messages. If you enable a second
console, labeled-tape messages will also continue to appear on the operator console.
The MEDIACOM ALTER CONSOLE command displays outstanding mount, drive-
usage, and unknown tape messages and then puts the current MEDIACOM process in
console mode.
To direct labeled-tape messages to a console other than the operator console with
MEDIACOM, log on as a super-group user (255,n) and enter at that terminal:
> MEDIACOM ALTER CONSOLE, DEVICE terminal-name
STORAGE - Detailed Status TAPE \ALM171.$TAPE1
BackupPID................... 1, 30
LDev........................ 20
PrimaryPID.................. 0, 30
State....................... STARTED
SubState....................