FAQnP ... Frequently asked questions and problems

all containers running but "Zabbix server" host item not reachable in UI

Thats because the default "Zabbix server" item in Zabbix is looking for "localhost" which isn't working in containers as it's normal. So to solve that problem you can:

• simple change "localhost" to "zabbix-agent" which points to the, hopefully also started, Zabbix Agent container.
• or, arguably better!, you remove the Zabbix Agent template from "Zabbix server" (while leaving the Zabbix server templates!) and create a new host "Zabbix agent" which you point to the zabbix-agent container and link the template there.

why are there so many containers with Docker Compose?

Because there are so many possible configuration combinations there are also a lot of docker-compose templates. The highlight here is on templates! They simply aren't supposed to be docker-compose up -d -f docker-compose_v3_ubuntu_pgsql_latest.yaml. You should instead copy the one you like and then tailor it to your needs. So for example if you choose Postgres as your DB copy the pgsql_latest to docker-compose.yml and just keep the services you need.

The agent container states "host [xxx] not found"

 22264:20210318:123205.124 no active checks on server [zabbix-server:10051]: host [722372e65167] not found

Every time a container is created it gets a new id/hostname unless you set the hostname: zabbix-agent or add ZBX_HOSTNAME=zabbix-agent to the env variables. Then you can create an Zabbix host with zabbix-agent as item.