Multiple connections
With Profile Container, multiple connections are supported by using VHD(X) difference disks. Profile Container is configured for multiple connections using ProfileType. When configuring Profile Container, ProfileType can be set to one of four modes. Parallels RAS allows you to configure these profile types from within Parallels RAS Console.
To select a profile type:
In the Profile Settings dialog, select the Advanced tab.
Select the Profile type option.
Select one of the four modes that are available. Multiple connections are not supported for Office Container.
The profile types are explained in the section below.
Mode 0 (Normal profile)
Sign on:
Client tries to attach the VHD(X) file directly. No difference disks are used. If concurrent access is attempted, it will fail with a sharing violation (error 20).
Sign out:
Client detaches the VHD(X) file.
Mode 1 (RW profile)
Sign on:
Client attempts to open the RW.VHD(X) difference disk with Read/Write access. If it is successful, it merges the difference disk to the parent. If it completes the merge, the RW.VHD(X) file is deleted.
Client creates a new RW.VHD(X) difference disk.
Client attaches the RW.VHD(X) as the Profile VHD.
Sign out:
Client detaches the RW.VHD(X) difference disk (the user's Profile VHD/X).
Client attempts to open the RW.VHD(X) difference disk with Read/Write access. If it is successful, it merges the difference disk to the parent. If it completes the merge, the RW.VHD(X) file is deleted.
Mode 2 (RO profile)
Sign on:
Client attempts to open the RW.VHD(X) difference disk with Read/Write access. If it is successful, it merges the difference disk to the parent. If it completes the merge, the RW.VHD(X) file is deleted.
Client attempts to delete the previous RO difference disk (if it exists).
Client creates the new RO difference disk.
Client attached the RO difference disk as the user's Profile VHD.
Sign out:
Client detaches the RO difference disk.
Client deletes the RO difference disk.
Client attempts to open the RW.VHD(X) difference disk with Read/Write access. If it is successful, it merges the difference disk to the parent. If it completes the merge, the RW.VHD(X) file is deleted.
Mode 3 (RW/RO profile)
Sign on:
Client checks to see if a RW.VHD(X) file exists. If it doesn't, the client takes the RW role and performs the same steps as ProfileType = 1. If the RW.VHD(X) file does exist, the client takes the RO role and does the same steps as ProfileType = 2.
General Information
RO difference disks are stored in the local temp directory and are named %usersid%_RO.VHD(X).
The RW difference disk is stored on the network next to the parent VHD(X) file and is named RW.VHD(X).
The merge operation can be safely interrupted and continued. If one client begins the merge operation and the operation is interrupted (e.g. the client is powered off), another client can safely continue and complete the merge. For this reason, both the RW and RO clients begin by attempting a merge of the RW.VHD(X).
Merge operations on ReFS file system, where the difference disk and the parent reside on the same ReFS volume, are nearly instantaneous no matter how large the difference disk is.
Merge operations can only be done if there are no open handles to either the difference disk or the parent VHD(X). For this reason, the RO client also attempts to merge the RW VHD(X) as it may be the last session to disconnect.
For more information, see https://docs.microsoft.com/en-us/fslogix/configure-concurrent-multiple-connections-ht.