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Getting Started with SmartOS

In this section:

SmartOS is a live image distribution of Illumos, designed specifically for the purpose of running virtual environments. The features of SmartOS that make it an attractive option for running virtual environments lends itself to the way it was designed. Specifically, you do not install SmartOS in the traditional sense. Instead, the running system is contained entirely within memory although you can store some data persistently on disk. Generally, the design of SmartOS and the benefits it provides breakdown in the following way:

  • Upgrades are trivial: This means no unnecessary complications working with patches. To upgrade a SmartOS release, you just reboot into a new image.
  • Increased disk space No need to use disk space on an OS install. All disk space is dedicated to virtual machines and user data.
  • Increased disk performance: Typically with other systems, you install the OS to a pair of mirrored disks and then pool the remaining disks for data. With SmartOS, you contain all your disks in the same RAIDZ pool, increasing performance.
  • Additional security: Most of the system files are read-only. In addition, /etc is re-created on each boot, making it much harder to exploit.
  • Increased stability: With other OSes, system commands become dysfunctional once root disks start to fail. This does not happen with SmartOS.
  • Purpose built: Much simpler to install and provision, especially when you have a large number of machines.

For details on the benefit of running SmartOS as a live image, watch this video.

The SmartOS ISO is a bootable CD image containing GRUB, the Illumos kernel, and the SmartOS boot archive. You can copy the image to any medium and load it on boot through any multiboot bootloader. This makes it easy to convert the image into a bootable USB thumbdrive or PXE boot image. You can even copy /platform to your Linux system, add an entry to the GRUB menu.lst file, and dual boot without needing to repartition.

You can find the default single user mode root password for a given release on the boot media in /platform/root.password. The default single user mode root password changes from release to release. Otherwise the root pas sword is simply "root".

System Requirements

The more memory you can dedicate to SmartOS the better due to it running as a live image:

  • A minimum of 1GB of RAM
  • 64-bit x86 CPU only

To take advantage of KVM features, SmartOS requires an Intel CPU with VT-x extensions in the following microarchitectures:

  • Nehalem
  • Westmere
  • Sandy Bridge
  • Ivy Bridge

...or later.

SmartOS will run in a virtual machine. However, if nested virtualization is unavailable, some HVM features will not function.

Creating a Persistent zpool

Everything on SmartOS is transient due to the nature of its design. That is, it does not persist across reboots and any changes made on the running system are destroyed as soon as the system is no longer running. This really is not a problem as you typically want changes to your data to persist, not changes to the running operating system or filesystem hierarchy.

For this reason, SmartOS includes a dataset setup script that runs automatically on boot. If you run SmartOS from an alternate form of media and want the dataset setup script to run on boot, ensure the following kernel command line option is set:


If you want to disable the dataset setup script:


This is not an installer and does not install the live image. The script is simply for data setup. You will still need to boot from live media.

As a distribution of the Illumos kernel, SmartOS uses ZFS as the filesystem and takes full advantage of all the inherent features of ZFS including data integrity preservation, support for snapshots and copy-on-write clones, support for high capacities, and RAID-Z support.

Further Reading

How to create a zone and How to create an HVM Virtual Machine give more detail about vmadm create.

For detailed information on ZFS and ZFS features, see the ZFS Administration Guide.

Discussion List

The smartos-discuss list is a forum for useful questions and answers - see the searchable archives here; sign up here.