Hello Sam,
It looks like we have not added a binary download or Dockerfile for RHEL9 yet, but you can compile from the source code... which is recommended anyway as it allows you to pick and choose just the modules you want. For example:
git clone
https://github.com/sflow/host-sflowcd host-sflow
make rpm FEATURES="PCAP TCP DROPMON"
Depending on which modules you select you may need to install some dependencies first (regrettably that part is not automatic). For examples see the Dockerfile for RHEL8:
Please raise an issue on the github site if you run into problems.
(And we'll add a Docker build for RHEL9 sometime this week.)
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Neil McKee
InMon Corp.