Use in a computer network

SM2 provides functions for the central online monitoring and control of monitored-data acquisition in a computer network.
The monitored data is independently recorded on each host in the network by a local SM2 monitoring program, and is exchanged between the hosts via a LAN. In this way, the online reports of all hosts can be output on any computer in the network.
There are also reports which output the combined monitored data of the various hosts.

All control statements for the acquisition of monitored data (changing monitoring cycles, switching monitoring programs, etc.) can be entered on any host for all computers in the network.

The SM2 functions for monitored-data acquisition in a network are also available in a HIPLEX network.

Prerequisites for using SM2 in computer networks

1. An MSCF connection of type CCS (Closely Coupled System) must exist between all hosts in the network.
   For further information on this connection type, refer to the “HIPLEX MSCF” manual [8].

2. The SM2 functions for monitored-data acquisition in a network can only be used for those computers in the network which run the same version of SM2.

3. SM2 must be started once on all computers in the network (e.g. with START-SM2) or at least loaded via the DSSM command START-SUBSYSTEM SUBSYSTEM-NAME=SM2.

Selecting hosts with SM2

The privileged statement SELECT-HOSTS selects the computers to which all subsequently entered SM2 statements are to be sent. This statement always applies to the user who issues it. Following the END statement and a restart, the default value applies again, i.e. SM2 statements are only executed on the local host.

The SHOW-SELECTED-HOSTS provides information on the selected hosts. This includes the time of the last monitored variable queried.

Users in a computer network

SM2 distinguishes between privileged users (“primary” and “secondary” administrators and other privileged users) and nonprivileged users. This also applies in a computer network.

It does not distinguish between the rights of local and remote users.
Users can have different rights on different hosts, depending on their privileges and the rights they have already been assigned. In particular, the primary administrator of a host can come from a different host. These primary administrators can be identified on the MEASUREMENT STATUS screen by the additional output of the host name.
The set of administration statements available may be restricted according to the rights of the user. As a result, the set of permitted statements may vary from one host to the next. Prohibited statements are rejected by the relevant hosts. If several hosts are selected, the statements of the first specified host are displayed in the user dialog.

Screen output

The screens containing the local data of a particular host are output in succession. These are followed by the screens of the next host, and so on. The system name in the top lefthand corner of the screen indicates which host to which the screen belongs.

Before the local screens of the individual hosts, screens showing combined data from the whole network can be output (GLOBAL, NSM and SHARED PUBSET reports):

• The GLOBAL report provides an overview of the utilization of all hosts in the network.

• The NSM report outputs data of the NSM subsystem for all hosts in the network.

• The SHARED PUBSET report shows the access to shared disk devices.

These reports only cover the hosts which have been previously selected by means of the SELECT-HOSTS statement.

Standard SM2 output file

The standard SM2 output file is created on every host on the home pubset. To enable the SM2 output files of the various hosts to be distinguished later on, the file name also includes the system name.

Restrictions for the computer network

1. The BS2000 /TART-TASK-MEASUREMENT command can only be used on the local host.

2. Scroll commands

   • Scrolling backward with - or -R is not supported across host boundaries; i.e. you cannot scroll back from the first report of one host to the last report of the previous host.

   • You can only change to the first report of the previous host using the scroll command -N (node) (see "Statements for nonprivileged users").

   • You can only access the reports containing combined monitored data using -N while scrolling backward.

   • The scroll command -- always displays the first selected report.

3. The monitored values of the individual hosts are only output together if the time also corresponds. The system clocks on all hosts should be synchronized as far as possible and the same monitoring cycle must be set in SM2.

   If no valid or new data exists, the following outputs are possible:

   • SHOW-SELECTED-HOSTS statement
     In the LAST BUFFER column, RSLT NOT VALID is output for the last monitored variable queried instead of the time.

   • GLOBAL and NSM reports
     In the column for the monitored variables, *** is output.

   • SHARED PUBSET report
     The message SOME DATA MISSED is output.

   • Local reports
     For local reports, the message NO DATA FROM xyz is output.

Dynamic IO configuration change

SM2 recognizes a dynamic IO configuration change and, if need be, automatically modifies the range of objects monitored.

 

The following table describes the behavior of the monitoring programs when adding a device/channel in the context of a dynamic IO configuration change:

Monitoring program	Behavior when adding a device/channel
DISK-FILE	No action
SAMPLING-DEVICE	Monitoring program is terminated internally and then restarted
SERVICETIME	Monitoring program is not restarted, even if the device belongs to the monitoring program definition
SYSTEM	Device is involved in the measurement, if it belongs to the monitoring program definition
TASK	Monitoring program is not restarted, even if the device belongs to the monitoring program definition
CHANNEL-IO	Monitoring program is terminated internally and then restarted, if monitoring program definition is *ALL
SAMPLING-CHANNEL *)	Monitoring program is terminated internally and then restarted

*) internal monitoring program

If a device/channel is removed, no monitoring program is terminated internally and then restarted. The device/channel is anymore visible in the SM2 datas, but the measurement values are always zero.