active check configuration update from [myhostname.com:10051] started to fail (gethostbyname() failed for 'myhostname.com: [3] Unknown server error)

Virt-guest is OVA deployed where vendor has "hardened".  Looks like "gethostbyname()" libraries required by "nsswitch.conf" are not installed.   Looks like Zabbix agent uses the "gethostbyname()" C function.   This is obsolete; use getaddrinfo() instead.

I also found the start-up systemd service startup for the Zabbix agent fails as the default "zabbix" userid cannot be found with the "hardened" environment.   I'm working with the vendor to get the appropriate libraries added.   

However, is there any plan to update the Zabbix Agent code to use non-obsolete functions.