Azure is changing so fast it can be difficult to keep up with all of its limitations (I am trying my best to keep this list up to date). Please verify any of the limitations listed on this page via the links at the bottom of this blog post. It is important to note some of these Azure limits if you are considering a large, production type of environment on Azure IaaS. Some of these limitations will stop you from being able to successfully deploy a large SharePoint production environment or other software to Azure.
My personal opinion is that Azure is currently good for dev & test, small to medium size non-mission critical farms and storage or backup needs. However, you should always investigate products and services yourself to see if they are the best choice for your needs. Going forward, I think Azure will grow into handling larger farms, mission-critical solutions and virtual networks in the future as it continues to get better almost every day (Microsoft is investing enormous amounts of time and money into the product). That being said, here are some limits or possible issues to consider:
Hardware (or virtual equivalent)
- Since Azure has added new Basic and Standard tiers of service, the limits of IOPS and number of disks you can attach to each VM differ, please see article below: http://msdn.microsoft.com/en-us/library/windowsazure/dn197896.aspx
- If you need your VMs to be up 24/7 you will need to create Availability Sets for times when MSFT has maintenance periods
- Each subscription has a 20 core limit by default. For example1 X-large machine and 3 large would hit the quota limit of 20. If you had 20 small machines with 1 core each, that would meet the same quota, etc.) To request a higher core count, see Windows Azure Support
Note that with the new “G” series (Godzilla) of SSD disks that were added recently, some of this may not apply.
- Max size of 2 TB in VM (I believe this changed on 4-14-14 from 1TB to 2TB – Please check Azure site)
- 5 concurrent storage accounts – by default, can request more I believe
- 500GB SQL Azure database max size – new as of 4/3/14
- 127 GB – Disk Size Limit for VM for OS Drive (usually your C: drive)
Managed SQL Backup Using SQL Server Agent
- Max 1 TB
- 30 days of retention
- Something to do with naming (sorry still checking on this)
*Other Note: Free to backup from your on-premises environment regarding bandwidth, but you pay for outgoing bandwidth to restore and the storage space you use for the backups.
I was recently at an Azure event and was told that running your own installation of the following software on Azure VMs is NOT officially supported:
- Exchange 2013
- Lync Server 2013
IP Addressing / IP Configuration
- I believe you can only assign 1 IP per NIC card (update 10/1/14 – multiple public IPs have now become available for Azure VMs & worker roles)
- You can keep one permanent IP per VM – see Build announcements 4/3/14 for clarification
- There was also some type of change where you can get 5 IPs per account so that you don’t have to keep a VM up and running to keep the same IP, however I need to check into this more to fully understand.
VHD / Image Size Limits
127 GB – This is usually caused from dynamically formatted images being used, Azure will convert it “its own way” and possibly cause the image to become huge. This is related to the disk size limit for an OS listed above.
Active Directory (*Check site for updates)
Instances Count: The more the merrier. This will depend on your Windows Azure subscription (typically 20 for a regular subscription is the maximum number).
- Is Your Application a Good Fit for Windows Azure? – MSDN
- Are There any Azure Limitations – TCSC
- Finding out Core Counts and other Available Resources via PowerShell in Azure – Scott Hoag
- Limitations / Items Supported on Azure Virtual Machines – Microsoft
- Azure Performance Guidance for SQL Server – Microsoft