anchor.diff:  
   ### <a id='blobstore'></a> External Blob Storage
   
  -Blobs are large binary files, such as PDFs or images. To store blobs for high availability, use external storage such as Amazon S3 or an S3-compatible service. 
  +Blobs are large binary files, such as PDFs or images. To store blobs for high availability, use external storage such as Amazon S3 or an S3-compatible service.
   
   You can also store blobs internally using WebDAV or NFS. These components run as single instances and you cannot scale them. For these deployments, use the high availability features of your IaaS to immediately recover your WebDAV or NFS server VM if it fails. <%= vars.contact_support %>
   
  
positive.code: 
  * **Vertical scaling**: Add memory and disk to each VM.
  
  * **Horizontal scaling**: Add more VMs that run instances of <%= vars.product_short %> components. 
  
  The type of apps you host on <%= vars.product_short %> determines whether you scale vertically or horizontally.
  
  For more information about scaling applications and maintaining app uptime, see the following topics:
  
  
negative.code: 
  Scaling horizontally means increasing the number of instances of VMs that run a functional component of a system.
  
  You can horizontally scale most <%= vars.app_runtime_abbr %> component VMs to multiple instances for high availability.
  
  You should also distribute the instances of components across different AZs to minimize downtime during ongoing operation, product updates, and platform upgrades. For more information about using AZs, see [Availability Zones](#azs).
  
  