Opengear ACM5000, User Manual

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Console Server & Router User Manual
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The results were from running tests 5 times in succession with no timeouts on any runs. However there are a number of
ways to increase the number of checks you can do:
Usually when using NRPE checks, an individual request will need to set up and tear down an SSL connection. This
overhead can be avoided by setting up an SSH session to the
console server and tunneling the NRPE port. This allows
the NRPE daemon to be run securely without SSL encryption, as SSH will take care of the security.
When the console server submits NSCA results it staggers them over a certain time period (e.g. 20 checks over 10
minutes will result in two check results every minute). Staggering the results like this means that in the event of a power
failure or other incident that causes multiple problems, the individual freshness checks will be staggered too.
NSCA checks are also batched. So in the previous example the two checks per minute will be sent through in a single
transaction.
10.4.5 Distributed Monitoring Usage Scenarios
Below are a number of distributed monitoring Nagios scenarios:
I. Local office
In this scenario, the console server is set up to monitor the console of each managed device. It can be configured to
make a number of checks, either actively at the Nagios server's request, or passively at preset intervals, and submit the
results to the Nagios server in a batch.
The console server may be augmented at the local office site by one or more Intelligent Power Distribution Units (IPDUs)
to remotely control the power supply to the managed devices.
II. Remote site
In this scenario the console server NRPE server or NSCA client can be configured to make active checks of
configured services and upload to the Nagios server waiting passively. It can also be configured to service NRPE
commands to perform checks on demand.
In this situation, the console server will perform checks based on both serial and network access.