...
set system name-server 8.8.8.8
file copy "https://cdn.juniper.net/xxxxxxx/jinstall-ppc-18.4R1.8-signed.tgz?/xxxxx xxxxx" /var/tmp/image-name.tgz
...
...
set system name-server 8.8.8.8
file copy "https://cdn.juniper.net/xxxxxxx/jinstall-ppc-18.4R1.8-signed.tgz?/xxxxx xxxxx" /var/tmp/image-name.tgz
...