A server farm is a collection of server machines acting together to host SharePoint services and workloads.
Web servers are servers that respond to user requests and render the SharePoint web pages. All web servers in a farm are mirrors of each other and are load balanced. The web server tier is composed of web servers or other servers that receive and respond to HTTP requests. Web servers host SharePoint web applications in Internet Information Services (IIS).
Application servers are used to describe any server that runs backend application services.
Some services are like: search service, PerformancePoint service or Excel Services etc.
The database tier hosts nearly all the data of your farm in SQL databases. This includes configuration databases, service application related databases, and content databases. All databases can be assigned to one database server or spread across multiple servers.
Here we will discuss about limits in SharePoint Online for Office 365 Midsize Business Plan.
- There is 500 MB storage per subscribed user.
- Total available tenant storage is 10 GB + 500 MB per user.
- The site collection quota limit is upto 100 GB per site collection. SharePoint admins can set storage limits for site collections and sites. The minimum storage allocation per site collection is 24MB.
- There can be only 20 site collection per tenant.
- There can have up to 2,000 subsites per site collection.
- Personal site storage limit is 7 GB per user. Personal site storage applies to a user’s SkyDrive Pro library and personal newsfeed.
- Public Website storage default limit is 5 GB but a SharePoint admin can allocate up to 100 GB.
- File upload limit is 250 MB per file.
- Number of user can be min of 1 to max of 250 users.
- You can invite upto 10,000 unique external users per month.