Host Not Found Using Proxy, Active Checks, and Private Networks

[smiz]

Hello all,

Using Zabbix 4.4.5

I have two machines to monitor on a private network. I've setup a Zabbix Proxy within that same network, which is pointed to a Zabbix Server OUTSIDE that network. The Server has a virtual IP assigned to it that the private network routes to.

None of the Zabbix Agents are showing Green in the Server, each one stating that the host is not found on the Zabbix Server for Active Checks.

no active checks on server [proxy.IP.Addr.ess:10051]: host [hostname] not found

• The hosts have been added into the Zabbix Server, exactly matching the hostnames in the agent conf file.
• Passive Checks have been disabled (StartAgent=0, Server= line is commented out)
• ServerActive= is set to the Proxy IP
• The Proxy is pointed to the Zabbix Server virtual IP.
• The hosts being monitored can ping the proxy, and the proxy can ping the server.
• The proxy has been added into Zabbix, and the monitored hosts are set to monitor by Proxy.
• MySQL is installed and configured on the Proxy server locally

I'm also seeing this error in Zabbix Server logs--

"zabbix_proxy:process.ipmi_manager.avg.busy" changed: Preprocessing failed for: {"data":{"boottime":1581675999,"uptime":555238,"hosts":3,"items":32,"item_unsupported":6,"require...
1. Failed: cannot extract value from json by path "$.data.process['ipmi manager'].busy.avg": no data matches the specified path

Lastly, due to using PHP 7.4.2, I had to pull some updates to Zabbix which were previously located here, but that branch has since been removed:

https://git.zabbix.com/projects/ZBX/repos/zabbix/compare/diff?targetBranch=refs%2Fheads%2Frelease%2F4.4&sourceBranch=refs%2Fheads%2Ffeature%2FZBX-17220-4.4&targetRepoId=152#frontends/php/include/validate.inc.php

Is there anything that stands out that I'm missing here; any advice? I can post configs, as needed. If nothing stands out, I think I'm going to just take this down to Zabbix 4.0 go from there again, I'm pretty stumped on this one.