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For application monitoring and log visualization of API nodes, we recommend Splunk - the free license should be sufficient for most uses.
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Other than application performance monitoring, Infinit.e will run functionally identically with our without Splunk. Splunk is not used for any of the ingest, search, analysis, aggregation, or visualization components.
Note also that the DB nodes do not use Splunk at all.
Splunk is not bundled with any of the Infinit.e RPMs (it is a commercial piece of software, not Open Source). It should ideally be installed before the config RPM (follow the instructions on the web site). If the config RPM is installed first, then it must be re-installed after Splunk (eg "rpm -U --force").
Installing infinit.e-config
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