checkmk ships Proxmox VE Special Agent to integrate Proxmox VE nodes/clusters into Monitoring. Unfortunately this requires a network connection to the Proxmox VE Port 8006 to use API via HTTPS.
Many of my nodes are not reachable directly for Checkmk due to security reasons and the result of check_mk_agent is pushed to Checkmk. The following solution is intended for cases where the Proxmox VE node is not directly accessible from the Checkmk server.
After a analysis of the integrated special agent, i migrated the special agent to an agent plugin to run in check_mk_agent either via HTTPS API (e.g. to the server running agent himself or any other reachable server) or using local pvesh binary to query the API using root@pam user. pvesh is much more slowly and should not be used on large environments and also async.
It produces the same output as the official Promox VE special agent including piggyback sections for Virtual Machines and Linux Containers (LXC). In most places, it (re)uses the source code of the Proxmox VE special agent. So this package is reduced to the agent plugin and configuration for bakery.
Version 0.1 is released on Github and checkmk Exchange.
Issues, pull requests and questions are welcome.