HP 3000 Manuals HP 3000 Manuals
Input Processes
Check
The Check process (DMCHECK.DESKMON.SYS) performs all the DeskMon checks,
with the exception of the STATSFIL checking. It receives control packets
through its IPC file (DMCHKIPC) and writes all packets it generates
(message packets and circular error message packets) into the main IPC
file (DMIPC), where the Report process will process them.
Every quarter hour, the Check process reads the time schedule from its
database to determine whether or not any checks are necessary. If checks
are required then it proceeds to perform them. The checks fall into
three categories:
* Non-HP DeskManager dependent checks.
* HP DeskManager dependent checks.
* External application checks.
* Non-HP DeskManager dependent checks do not require any HP
DeskManager resources, even though they may check items related to
HP DeskManager.
* Job status--performed by calling the JOBINFO intrinsic.
* IPC file status--made by opening the IPC file, reading the
current EOF position and checking this against the
configured DeskMon entry.
* Hung Master Trucks--performed by checking the status of the
Master Truck process in relation to the amount of CPU used
since the last check. If the process is BIO (Blocked on
I/O) and has used no CPU since the last check, it is
assumed to be "hung".
* HP DeskManager dependent checks require access to the HP
DeskManager database and the PROCMGMT file. They cannot be
performed during HP DeskManager operations that require exclusive
access to the HP DeskManager database.
* Mail status--performed by reading the appropriate status
flags within the PROCMGMT file.
* Mail Queue--performed by reading the TSNFILE file and
checking the details against the configured DeskMon
entries.
* Dataset status--obtained from the HP DeskManager database
by DBINFO calls to the appropriate datasets.
* External Application checks are created as sons of the Check
process. The $STDIN of the external application is redirected
from $NULL, and the $STDLIST is automatically redirected to a
DeskMon created and controlled file. DeskMon also creates a timer
process as a son, passing to it the "Maximum program execution
time" configured in DeskMon. The Check process sleeps while the
external application is active. In case the external application
does not complete, the timer process is used to ensure that the
Check process awakes after the configured maximum time.
If the external application cannot be created or exceeds its
maximum time, a suitable message packet is sent to the Report
process. If the external application terminates normally, its
success or failure is returned to the Check process by the JCW
specified in the DeskMon configuration. If the JCW cannot be
found by the Check process, a suitable message packet is sent to
the Report process. If the JCW is not equal to zero, DeskMon
assumes the external application detected an error and wants a
message to be sent. This message is taken from the first text
line that the application wrote (retrieved from the file DeskMon
created for the redirected $STDLIST). If no text can be found then
a suitable message packet is generated and sent. If the message
is being sent to a Report Category that includes a "Send HPDesk
message" option, the complete output of the external application
(the redirected file) will be included in the HP DeskManager
message.
LogScan
The LogScan process (DMLOGSCN.DESKMON.SYS) checks the HP DeskManager
STATSFIL.MAILDB.HPOFFICE file for exceptions listed in the DeskMon
configuration.
The first action of this process is to establish the current EOF marker
in STATSFIL by opening the file, reading the current EOF, and then
closing the file. The LogScan process then sleeps for the time specified
by the DMSTATSTIME JCW. When the sleep time expires, the process re-opens
STATSFIL, scans from the previous EOF to the current EOF reporting any
exceptions, records the current EOF, and then closes STATSFIL. This
process is then repeated at intervals specified by DMSTATSTIME.
The LogScan process requires that the STATSFIL file is not built as a
circular file (which is the default). To do this you can either purge or
rename the current file while HP Desk is not running, and rebuild the
file using the following command:
:BUILD STATSFIL.MAILDB.HPOFFICE;REC=-85,15,F,ASCII;DISC=20000,32,1
You can ensure that the Mailmaint rebuilds the file correctly by editing
the MAILMNT2.MAILJOB.HPOFFICE job stream file. The DESKMON JCW should be
set to "ON" rather than "OFF". You should also check that the size of
the file built is suitable for your system. Either the file must be
large enough to ensure that it does not get full between each running of
the Mailmaint, or ensure that it is recreated more often.
DMJCL
The DMJCL process (DMJCL.DESKMON.SYS) allows the DeskMon reporting
process to be used to display messages that are not generated by a
specific DeskMon check. See Chapter 6 for more details.
NSReceive
The NSReceive process (DMNSRECV.DESKMON.SYS) names a socket "DESKMON" and
waits for remote systems to call up this socket. When the socket is
called up, NSReceive creates a virtual circuit between the two systems
receiving and acknowledging a packet. This packet is then written to the
main DeskMon IPC file DMIPC.
DSReceive
The DSReceive process (DMDSRECV.DESKMON.SYS) is initiated as a slave
process by a remote system using the PTOP intrinsics. It is controlled
by the DSSend process on the system that initiated it but it does have
the option to accept or reject the packets it is being sent. It rejects
packets if the DeskMon reporting process is not active on the local
system, signified by the DSReceive process being able to gain exclusive
access to the DMDSLOCK.DESKMON.HPOFFICE file. If the packet is accepted,
it will be written to the main DeskMon IPC file DMIPC.