Raspberry pi gpio serial port

[rick pickle]

How to find port no of serial device on gpio.
This is my first experience with zabbix so still alot to learn.

Project;
I want to read data from a Morningstar sunsaver MPPT solar charger through a Morningstar PC meterbus adapter connected to the gpio pins of raspberry pi 3.

So far;
I have installed Zabbix 5.2 on a raspberry pi 3 and imported templates for the sunsaver mppt. On the raspberry I have activated TTL serial port as a "serial interface" on GPIO 14 and GPIO 15 and disactivated bluetooth. According to the instructions i followed its at /dev/serial0
when i list my devices it shows the serial0 gpiochip1 mmcblk0p2 serial0 tty26 tty50 vcio vhci

The com settings for the PC meterbus adaptor are;
9600 Baud
8 data bits
1 or 2 stop bits
No parity
No hardware control

when setting up an interface to a host in zabbix it asks for
SNMP
IP address -
DNS name -
conect to IP/DNS -
port -
So if I type "serial0" into the DNS name field and opt for connect to DNS what do i use as my port number? how or where do i set baud rate?

any help would be great, I feel like im missing something here.

[rick pickle]

I went with serial0 for DNS and port 161, all accepted ok.

So with all installed I shut down and relocate my Raspberry pi to the shed where the MPPT sunsaver lives. with no internet the browser wont find the zabbix IP 192.168 etc.
If i relocate back to the house and the internet it opens fine.

Do i need a 'live' internet connection permanently to use zabbix or just to start up?

I dont really understand whats going on here, any help would be great.

I was going to use an old linksys as a LAN router but wasnt going to connect it to the internet once everything was installed and set-up, im not sure if that is possible now?