Troubleshooting guide

11 — 5620 SAM maintenance base measures
Alcatel-Lucent 5620 Service Aware Manager 11-7
5620 SAM
System Administrator Guide
Performance base measures
For networks, commonly available tools such as ping, which measures round trip
time using ICMP, can be used to determine quantities such as packet loss and round
trip delay. See the ping command information in this guide, and the 5620 SAM
Troubleshooting Guide, for more information about performing the commands.
• Packet loss is defined as the fraction of packets sent from a measurement agent to
a test point for which the measurement agent does not receive an
acknowledgement from the test point. Acknowledgements that do not arrive
within a pre-defined round trip delay at the measurement agent are considered
lost.
• Round trip delay is defined as the interval between the time a measurement agent
application sends a packet to a test point and the time it receives
acknowledgement that the packet was received by the test point.
You can baseline the packet loss results and round trip delay times for specific NMS
LAN and network scenarios. Record those results for future baselines against
regularly run packet loss and round trip delay tests.
Reachability base measures
System reachability is important in business-critical applications. Service
reachability components are:
• Can the customer reach the service? (reachability)
• If so, is the service available for customer use? (service availability)
• If not, how frequently and how long do service outages last? (service outage
duration)
The types of measures and baselines necessary to ensure reachability and availability
are network-dependent, and vary depending on the topology of the network, the
networking technologies used to move data, and the types of equipment used.
Reachability
A test point is reachable from a testing measurement agent when the agent can send
packets to the test point and receive a response from the test point that the packet was
received. The ping test and the OAM diagnostics using the 5620 SAM or device CLI
can test reachability. The results from these tests should be recorded for future
baselining.
These tests can be performed when you troubleshoot a customer service, or when you
perform SLA tests before you enable a customer service.
Service availability
The network between a measurement agent and a test point is considered available
at a given time when the measured packet loss rate and the round trip delays are both
below pre-defined thresholds. The threshold values are dependent on network
topology. The ping test and the OAM diagnostics using the 5620 SAM or CLI to a
device can test service availability. The results from these tests should be recorded
for future baselining.
Release 13.0 R2 | May 2015 | 3HE 09815 AAAB TQZZA Edition 01