Zabbix_sender send data about host on proxy

[Darkhunter]

Hello, I have got backup server, which isnt on any proxy.
I made script using zabbix_sender to send info about backup from servers, which are on proxy. On servers, which are not on proxy this command works:

zabbix_sender -c /etc/zabbix/zabbix_agentd.conf -s $server -k backup_error -o 1

But on servers on proxy it doesnt, because they dont have specified full domain name.
What can I do?