Member Avatar for lewashby

I'm trying to install CentOS on my Linux Mint desktop through Oracle's VirtualBox. The instalation screen says it's installing to sda1 and that's it's mount points are /boot -> 500 MB, / -> 5.02GB, & 614 MB. Is this safe or is there a chance this is going to mess something up on my current desktop? I'v never installing anything through a virtual machine before. Thanks.

  • 3 Contributors
  • 3 Replies
  • 341 Views
  • 1 Hour Discussion Span
  • Latest Post Latest Post by lewashby

Dani AI

Generated

Short answer: the CentOS installer is showing the guest's disk and partitions, not the host machine. As and pointed out, VirtualBox presents a virtual hard drive to the guest OS; that device shows up inside the installer as /dev/sda. Unless raw (physical) disk access was explicitly configured, the installer will only touch the VM’s virtual-disk file, not the Mint host partitions.

Common checks to confirm the target is the VM disk:

  1. In VirtualBox Manager select the VM -> Settings -> Storage. The attached hard disk entry shows the filename and full path (the .vdi/.vmdk).
  2. Open File -> Virtual Media Manager to see each virtual disk’s Location and whether it’s dynamically allocated or fixed size.
  3. In the CentOS installer’s “Installation Destination” screen check the device size and name; if it matches the virtual disk shown in VirtualBox, the installer is operating on the VM. If the listed drive size is the full size of the physical drive, power off and re-check settings.

Those three partition sizes in the installer (500 MB, ~5 GB, ~614 MB) are partition allocations inside the VM (commonly /boot, root, and swap). That layout is normal for a small test VM. Raw-disk access is not the default and requires deliberate setup, so the presence of /dev/sda in the guest does not imply any host disk changes.

Practical safety tips: create a small test VM first (10–20 GB) to practice the installer, take snapshots if experimenting, and keep a host backup of critical data. After testing, remove the VM through VirtualBox Manager (and optionally “Delete all files”) to clean up any .vdi/.vmdk files or snapshots.

Recommended Answers

All 3 Replies

Member Avatar for JorgeM

You shouldnt be concerned with your desktop. The main benefit for the VM app is that the VMs are installed within a few files stored on your hard drive. no other changes (with regards to the VMs) affect your host computer. When you are done with the VM, you simply delete the folder containing these files (2-5 or so) and that's it.

I cant comment on the CentOS specifically because i'm not well educated on linux systems.

Member Avatar for rubberman

JorgeM pretty much hit this on the head. All the data in a VirtualBox VM are stored in system files. You do want to use the incremental expansion option for the virtual drive though, since it will not take up more space on your system disc than necessary - growing the file only when needed. So, if you allocate 50GB of space, but are only using 20, then it will only take 20GB of space (more or less). Also, with snapshots, you can roll the VM back to an earlier state very easily if needed, such as a bad update or such.

So, if you decide you don't want CentOS on the system any longer, VirtualBox has a "delete" option for your VM's that will give you the opportunity to get rid of the VM as well as all associated files.

Member Avatar for lewashby

Thanks.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.