Collecting performance statistics
Overview
Performance statistics provide information about physical equipment, routing, and other NE properties for monitoring and troubleshooting purposes. See the Statistics Search Tool for the MIB-based performance statistics that the NFM-P supports.
Performance statistics collection is enabled using a MIB statistics collection policy and associating the policy with one or more NEs or specific objects within the NEs, for example, ports. For greater efficiency and collection granularity, the following types of MIB statistics policies are available:
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NE MIB statistics policies—define collection at the NE level
An NE MIB statistics policy contains a list of the MIB entry policies that are invoked for all objects on the NE.
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specific MIB statistics policies—define collection at the object level
A specific MIB statistics policy contains the same list of MIB entry policies as an NE MIB statistics policy, but the MIB entry policies are applied only to the objects specified in the specific MIB statistics policy. A specific MIB statistics policy uses the concept of a monitored class, which is the type of object on which to collect statistics, for example, a port or service site. The monitored object instances must be specified in the specific MIB statistics policy. For example, if port is selected as the monitored object, then the actual ports in the network to which the policy applies must be specified, and become part of the policy.
Before the NFM-P performs a statistics collection based on a MIB statistics policy, it checks for duplicate collection requests, such as when the same object is included in an NE MIB policy and a specific MIB policy. If a duplicate is found, the NFM-P performs the collection on the object based on the specific policy rather than on the NE policy.
For performance reasons, Nokia recommends using NE MIB policies to collect statistics from all instances of an object on an NE, and specific policies to enable or disable collection for specific NE objects. This is a much more efficient use of NE resources than using a specific policy in which each object instance is specified. For example, you can configure an NE MIB policy to collect OSPF routing statistics on all the routing instances of the NE, and use a specific MIB policy to collect statistics on a subset of the routing instances.
Specific and NE MIB policies can operate together to streamline statistics collection. For example, to collect network port statistics at 5-min intervals and access port statistics at 15-min intervals, you can create an NE MIB policy for all ports with a 15-min collection interval and create a specific policy for network ports with a 5-min collection interval. At every third interval, when the two policy activations coincide, the NE policy is used and duplicate collection is prevented.
NE MIB policies can be specified in NE discovery rules to ensure that statistics collection starts immediately after the NE is discovered. Specific MIB polices must be updated manually for specific objects on the new NE after it is discovered or new objects are created.
Specific MIB policy settings override NE MIB policy settings.
Note: To view statistics on the NFM-P GUI, you must set the Administrative State parameter of the MIB policy to UP and the Polling Admin State parameter must be set to UP.
Table 3-1: MIB statistics policy overrides
For a given object | ||
---|---|---|
NE MIB policy |
Specific MIB policy |
Action |
Collect |
Collect |
Statistic is collected once |
Do not collect |
Do not collect |
Statistic is not collected |
Collect |
Do not collect |
Statistic is not collected |
Do not collect |
Collect |
Statistic is collected |
For top-down performance statistics configuration, choose Tools→Statistics→MIB Policies from the NFM-P main menu to systematically configure statistics for the network. For bottom-up performance statistics configuration, configure the MIB entry policy from the Statistics tab of the properties form for a specific object.
GNE performance statistics support
The NFM-P supports the collection of a limited set of statistics counters from standard system, interface, and routing MIBs on GNEs. These statistics are processed and presented in the same manner as statistics from other devices. You can view GNE statistics on the Statistics tab of a GNE interface properties form, retrieve them using the XML API, and display them graphically using the NFM-P Statistics Plotter.
Note: If persistent SNMP indexes are not enabled on a GNE, one or more GNE interface indexes may change after a GNE reboots. This can cause a mismatch between the statistics records collected before the reboot and the current interface indexes. The NFM-P takes no action to identify or correct such a mismatch.