CONFIG_TEXT: There may not be enough free space on /tmp.
You may need to set TMPDIR to point to a directory with more free space.
Not enough disk space for /tmp partition
Contact server administrator and discuss a possibility to free-up disk space for the /tmp partition or make a new partition to mount the /tmp directory on the KVM slave server to create the custom template using the VPS.
Note: Disk space management is an administrative task and beyond of SolusVM Support scope. It should be handled by server administrator.