The problem is that your hostname is not pingable. System can not resolve the name. You can fix it by adding hostname to the /etc/hosts/file. Hostname should be associated with the system ip

/usr/local/vesta/bin/v-list-sys-ips; # list system ips

IP NETMASK NAT OWNER U_WEB_DOMAINS
--------- --------- --------- --------- ---------
XXX.XXX.XXX.XXX 255.255.255.248 NULL admin 3

hostname; # get hostname
domain.com

echo "XXX.XXX.XXX.XXX domain.com" >> /etc/hosts

src: https://forum.vestacp.com/viewtopic.php?f=10&t=4525

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