These steps cover how to install Ubuntu Server Linux into your empty virtual or real machine. (The instructions are similar, but may vary somewhat, for Debian Linux.)
Download Ubuntu Server 12.04 LTS, and burn it to a CD if installing on a real machine; otherwise, attach the download to your virtual machine's CD/DVD drive.
Answer all the region related questions and choose to Install Ubuntu Server.
For hostname, enter a2server
Under Partition Disks, choose "Guided - use entire disk" (no LVM).
Choose SCSI1 (or whatever other disk appears), and (two screens later) confirm "Write the changes to disks."
If you are installing Debian, and are prompted for a domain name or the root user password, leave them blank.
Enter user1 as the full name for the new user, and as the username for your account
Choose apple2 as the password, verify by retyping, and then confirm weak password
Choose not to encrypt your home directory
If you require an HTTP proxy, enter it, or leave it blank if not.
Choose yes to Install the GRUB boot loader to the master boot record
Choose no automatic updates
Choose OpenSSH under Software Selection (and, for Debian, Standard System Utilities)
Click Continue to reboot
When prompted, log in with username user1 and password apple2.
If you installed Debian rather than Ubuntu, type:
sudo sed -i '0,/-eq 0/s/-eq 0/-ge 0/' /etc/profile
When you're back at the prompt, type
sudo shutdown -h now which will turn off the (virtual) machine.
Recommended: If you are using a virtual machine, take a snapshot you can return to this point if necessary.
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