Category: Server Virtualization

Linux Container 0

Operating System Level Virtualization (Part 2) – Implementations Comparison

These days, everyone knows what’s Cloud Computing and cloud based services are using for speedup deployment of organizations services. Operating System Level Virtualization or Containers helping system architectures and administrators to achieve the goals. There are many implementations for containers that today, those methods are compatible with different hardware architectures and operating system.

You may know that Unix has OS Level Virtualization from past years and this technology is very older than other virtualization such as Full Virtualization or Paravirtulization.

Full Virtualization (VMware ESXi, Hyper-V) and Paravirtualization (Xen, UML) provides different guest OS but there is no way to use different guest OS when you are using containers. Of curse, some solutions are under development.

iSCSI vs Fiber Channel 0

Guest Connected vs RAW Device Mapping (RDM)

RAW Device Mapping (RDM) is one of oldest VMware vSphere features which introduced to resolving some limitation on virtualized environments such as virtual disks size limitation and deploying services top of fail-over clustering services.

You can use a raw device mapping (RDM) to store virtual machine data directly on a SAN LUN, instead of storing it in a virtual disk file. You can add an RDM disk to an existing virtual machine, or you can add the disk when you customize the virtual machine hardware during the virtual machine creation process.

Provisioning Types Comparison 0

VMDK Write Performance on Different Provisioning Types

VMDK (Virtual Machine Disk) has been designed to mimic the operation of physical disk. Virtual disks are stored as one or more VMDK files on the host computer or remote storage device, and appear to the guest operating system as standard disk drives.

VMware supports three provisioning types:

Thin Provisioned
Thick Provisioned
Eager-zeroed Thick Provisioned