title: Azure back up vs Snapshots
body: <p>I'm an azure newbie and just trying to understand Azure better. My questions are specific to backing up Linux VMs in Azure. Please help me in understanding it better.</p>
  
  <p>I read that Azure backup takes snapshots and then uploads them to the vault. I'm trying to understand how using 'Azure backup' to backup a VM is different from taking the snapshots of OS Disk and data disk of azure VM via "az vm" cli commands?</p>
  
  <p>What exactly is the vault here? Is it internally implemented as a storage account with blob container or is it something similar to the Glacier in AWS?</p>
  
  <p>Which is better cost wise, azure backup or osdisk snapshots?</p>
  
  <p>If both the options are similar, i.e using azure backup or taking a snapshot of OS disk/Data disks. Is there an advantage of using one over the other?</p>
  
  <p>Are the Snapshots of OS disk taken in Azure global in nature? Can they be accessed from any other geos?</p>
  
  <p>In the azure portal, snapshots, what is "snapshot state"? Why is the snapshot state "Unattached" for me even after spinning off a VM from the snapshot disk?</p>