Hi Duc,
Regarding the use of third-party monitoring tools, we do not have any specific recommendations or best practices on this subject as these are third-party tools that fall outside of the scope of Imperva Support.
I can provide you with documentation for configuring SNMP for monitoring Imperva appliances which you can find on the link below:
https://docs.imperva.com/bundle/z-kb-articles-km/page/866b7f14.html
With regards to which tools work better than others, this would be a matter for your Sys Admins to decide and I'm afraid we cannot offer any recommendations on the use of third-party tools.
Some tools require the installation of an Agent on the device which you intend to monitor. It is important to note that the installation of any third party software on any Imperva appliance is not supported, so whichever monitoring tool you decide to use, it must not require the installation of an Agent or similar tool as this is unsupported.
Best,
Vihar
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Vihar Desai
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