What is Host Pool
Collection of one or more virtual machines (VMs) that serve as session hosts
Providing virtual desktops or remote applications to users
Efficient management, scaling, and maintenance of the virtual desktop infrastructure

Example Host Pool
A company Acme Corp, with multiple departments
Sales, Marketing, and Engineering. Each department has different host pool
Sales Department Host Pool
Host pool contains VMs with applications specific to the sales team
Marketing Department Host Pool
Host pool contains VMs with applications specific to the Marketing team
Engineering Department Host Pool
Host pool contains VMs with applications specific to the Engineering team

Host Pool Type
Personal host pool
Each user is assigned a dedicated session host VM
Individual desktop experience
Settings, data, and applications remain the same between sessions
Example:
A company assigns dedicated VMs to their executives and managers for personalized and consistent virtual desktop experiences
Assignment Type
Direct
Administrators manually assign specific session host VMs to individual users
Automatic
Azure Virtual Desktop automatically assigns a session host VM to users when they first log in to the host pool
Pooled host pool
Multiple users to share a set of session host virtual machines (VMs) within a host pool
Users are dynamically assigned an available session host VM from the pool
Two primary load balancing algorithms available for pooled host pools
Breadth-first load balancing
This algorithm distributes user sessions across the maximum number of available session host VMs in the host pool
Example
Pooled host pool with 4 session host VMs maximum session limit 6 , If there are 16 concurrent user sessions each VM will have 4 sessions on average maintaining a balanced distribution
Depth-first load balancing
This algorithm fills each session host VM to its maximum session limit before moving on to the next VM
Example
Pooled host pool with 4 session host VMs maximum session limit 6 , If there are 16 concurrent user sessions each VM will have maximum session limit then only move to next session

Application Group Type
Logical grouping of applications
App groups allow administrators to organize and manage application
Two primary app group types
Desktop App Group
Provides users with a full desktop experience
Allowing access to all applications session host VMs within the host pool
A desktop app group named Desktop Application Group
Automatically created when a host pool is created
Not support to create another desktop app group in the same host pool while a desktop app group exist
Example :
Software development team requires access to a complete Windows 10 desktop experience with various integrated development environments (IDEs), version control tools, and other applications
RemoteApp  Group
Provides users access to individual applications installed on session host VMs Instead of presenting an entire desktop environment
You can create multiple remote app group as your requirement
Example:
A sales team needs access to a customer relationship management (CRM) application and a presentation tool
RemoteApp app group with these applications and assigns it to the sales team members
Application groups User Assignment
A user can be assigned to both a desktop app group and one or more RemoteApp app groups in the same host pool.
Users can only launch one type of app group per session
Workspace
A workspace is a logical grouping of application groups.
Each application group must be associated with a workspace for users to see the desktops and applications published to them

complete setup  Guide click the below link 

https://rijoskill.com/get-started-with-azure-virtual-desktop-a-complete-tutorial/ 

​What is Host PoolCollection of one or more virtual machines (VMs) that serve as session hostsProviding virtual desktops or remote applications to usersEfficient management, scaling, and maintenance of the virtual desktop infrastructureExample Host PoolA company Acme Corp, with multiple departmentsSales, Marketing, and Engineering. Each department has different host poolSales Department Host PoolHost pool contains VMs with applications specific to the sales teamMarketing Department Host PoolHost pool contains VMs with applications specific to the Marketing teamEngineering Department Host PoolHost pool contains VMs with applications specific to the Engineering teamHost Pool TypePersonal host poolEach user is assigned a dedicated session host VMIndividual desktop experienceSettings, data, and applications remain the same between sessionsExample:A company assigns dedicated VMs to their executives and managers for personalized and consistent virtual desktop experiencesAssignment TypeDirectAdministrators manually assign specific session host VMs to individual usersAutomaticAzure Virtual Desktop automatically assigns a session host VM to users when they first log in to the host poolPooled host poolMultiple users to share a set of session host virtual machines (VMs) within a host poolUsers are dynamically assigned an available session host VM from the poolTwo primary load balancing algorithms available for pooled host poolsBreadth-first load balancingThis algorithm distributes user sessions across the maximum number of available session host VMs in the host poolExamplePooled host pool with 4 session host VMs maximum session limit 6 , If there are 16 concurrent user sessions each VM will have 4 sessions on average maintaining a balanced distributionDepth-first load balancingThis algorithm fills each session host VM to its maximum session limit before moving on to the next VMExamplePooled host pool with 4 session host VMs maximum session limit 6 , If there are 16 concurrent user sessions each VM will have maximum session limit then only move to next sessionApplication Group TypeLogical grouping of applicationsApp groups allow administrators to organize and manage applicationTwo primary app group typesDesktop App GroupProvides users with a full desktop experienceAllowing access to all applications session host VMs within the host poolA desktop app group named Desktop Application GroupAutomatically created when a host pool is createdNot support to create another desktop app group in the same host pool while a desktop app group existExample :Software development team requires access to a complete Windows 10 desktop experience with various integrated development environments (IDEs), version control tools, and other applicationsRemoteApp  GroupProvides users access to individual applications installed on session host VMs Instead of presenting an entire desktop environmentYou can create multiple remote app group as your requirementExample:A sales team needs access to a customer relationship management (CRM) application and a presentation toolRemoteApp app group with these applications and assigns it to the sales team membersApplication groups User AssignmentA user can be assigned to both a desktop app group and one or more RemoteApp app groups in the same host pool.Users can only launch one type of app group per sessionWorkspaceA workspace is a logical grouping of application groups.Each application group must be associated with a workspace for users to see the desktops and applications published to themcomplete setup  Guide click the below link https://rijoskill.com/get-started-with-azure-virtual-desktop-a-complete-tutorial/    Read More

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