virtualmin restore-domain always get killed

Hi,

i was upgrading my old hosting server to a new one. but i'm having trouble restoring big backup data. (7GB)

i already split the backup per domain, even per user. but the process always exit with "killed" status right after configuring apache

below are the output

Checking for missing features .. .. all features in backup are supported

Starting restore.. Extracting backup archive files .. .. done

Re-creating virtual server ditptksd.go.id .. Creating administration group t95639 .. .. done

Creating administration user t95639 ..
.. done

Creating aliases for administration user ..
.. done

Adding administration user to groups ..
.. done
Creating home directory ..
.. done

Creating mailbox for administration user ..
.. done

Adding new DNS zone ..
.. done

Adding to email domains list ..
.. done

Adding default mail aliases ..
.. done

Adding new virtual website ..

Adding webserver user www-data to server's group ..
.. done

Performing other Apache configuration ..