OpenVMS Cluster Systems - OpenVMS Systems - HP

Maintaining an OpenVMS Cluster System
10.13 Cluster Performance
DECamds collects and analyzes data from multiple nodes (VAX and Alpha)
simultaneously, directing all output to a centralized DECwindows display.
DECamds helps you observe and troubleshoot availability problems, as follows:
• Alerts users to resource availability problems, suggests paths for further
investigation, and recommends actions to improve availability.
• Centralizes management of remote nodes within an extended LAN.
• Allows real-time intervention, including adjustment of node and process
parameters, even when remote nodes are hung.
• Adjusts to site-specific requirements through a wide range of customization
options.
Reference: For more information about Availability Manager, see the
Availability Manager User’s Guide and the Availability Manager web site,
which you can access from the Compaq OpenVMS site:
http://www.openvms.compaq.com/openvms/
For more information about DECamds, see the DECamds User’s Guide.
10.13.4 Monitoring LAN Activity
It is important to monitor LAN activity on a regular basis. Using the SCA
(Systems Communications Architecture) Control Program (SCACP), you can
monitor LAN activity as well as set and show default ports, start and stop LAN
devices, and assign priority values to channels.
Reference: For more information about SCACP, see the OpenVMS System
Management Utilities Reference Manual: A–L.
Using NCP commands like the following, you can set up a convenient monitoring
procedure to report activity for each 12-hour period. Note that DECnet event
logging for event 0.2 (automatic line counters) must be enabled.
Reference: For detailed information on DECnet for OpenVMS event logging,
refer to the DECnet for OpenVMS Network Management Utilities manual.
In these sample commands, BNA-0 is the line ID of the Ethernet line.
NCP> DEFINE LINE BNA-0 COUNTER TIMER 43200
NCP> SET LINE BNA-0 COUNTER TIMER 43200
At every timer interval (in this case, 12 hours), DECnet will create an event that
sends counter data to the DECnet event log. If you experience a performance
degradation in your cluster, check the event log for increases in counter values
that exceed normal variations for your cluster. If all computers show the same
increase, there may be a general problem with your Ethernet configuration. If, on
the other hand, only one computer shows a deviation from usual values, there is
probably a problem with that computer or with its Ethernet interface device.
The following layered products can be used in conjunction with one of Compaq’s
LAN bridges to monitor the LAN traffic levels: RBMS, DECelms, DECmcc, and
LAN Traffic Monitor (LTM).
Maintaining an OpenVMS Cluster System 10–23