Recovering from I/O Errors
Note that files created on a virtual 3800 can print on any real spooling device sup­
ported by VM/SP. However, if a file that was created on a virtual 3800 is printed
on another real printer (for example, a 1403 or a 3211) all 3800 unique control
information is ignored by the real printer. Further, while print lines of 204 bytes
are allowed by the 3800, lines will be truncated if printed on a real printer with a
smaller maximum line length (for example, a 1403 or a 3211).
When an I/O error occurs while a virtual 3800 spool file is printing on a real 3800, the VM/SP operator can specify the BACKSP AC command with the FILE param­
eter to recover from the error. The BACKSP AC command with the FILE parame­
ter restarts the spool file at the beginning and reloads the real 3800 with the control
information originally specified in the SETPRT command.
Displaying Control Information
The CP QUERY command enables G-, B-, and D-privilege users to display the
names of the character arrangement tables, copy modifications, and FCB currently
in effect for a spool file or virtual printer. In addition, the QUERY command dis­
plays the characteristics of the virtual 3800 that were established when the virtual
device was defined. Finally, the user can determine where 3800 load commands
are found in a file (not at all, at the beginning, or throughout).
The VM/SP operator can use the QUERY command to determine the image
library and form loaded on the real 3800. Further, the VM/SP operator can
determine which virtual 3800 spool files are being accepted for printing by the real
printer: those containing no 3800 load commands, those with 3800 load com­
mands only at the beginning, or those with 3800 load commands throughout (as
long as the class and FORMS match). The VM/SP operator specifies on the CP
START command which spool files the real 3800 accepts for printing.
IBM 3800 Printing Subsystem 299
Joumaling Logon, Autolog, and Link Commands LOGON, AUTOLOG, and LINK Journaling attempts to detect and record certain
occurrences of the LOGON, AUTOLOG, or LINK commands. Using the
recorded information, an installation may be able to identify attempts to logon to VM/SP by users that issue invalid passwords. Also, the installation may be able to
identify users that successfully issue the LINK command to protected minidisks not
owned by that user.
Briefly, LOGON, AUTOLOG, and LINK journaling works like this. While jour­
naling is turned on, CP monitors all occurrences of the LOGON, AUTOLOG, and
LINK commands. CP keeps count of the number of times a user issues one of
these commands with an invalid password. When this count exceeds an installation
defined threshold value, CP optionally:
Writes a record to the accounting data set to record the incident
Rejects subsequent LOGON, AUTOLOG, or LINK commands issued by the
user Sends a message to an installation-defined user identification to alert the instal­
lation to the incident
Also, each time CP detects that a user has successfully issued a LINK command to
a protected minidisk not owned by that user, CP optionally records the incident by
writing a record to the accounting data set. A protected minidisk is a minidisk
whose password is anything but ALL for the type of LINK attempted.
For a description of the accounting records that CP writes for LOGON, AUTOLOG, and LINK journaling, see the section "Accounting Records." The SYSJRL macro instruction, the SET command, and the QUERY command
enable an installation to control LOGON, AUTOLOG, and LINK journaling. To
make journaling available and to specify options, code the SYSJRL macro instruc­
tion in module DMKSYS. Instructions for coding this macro instruction are in the
VM I SP Planning Guide and Reference. To turn journaling on or off, use the class
A SET command. To determine whether journaling is on or off, use the class A
QUERY command. 300 VM/SP System Programmer's Guide
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