Scenario: A Citrix Engineer has two datacenters: Site A, the main datacenter and Site B, the secondary datacenter. Both datacenters have Citrix App Layering 4.3 installed.
How can the engineer ensure that all layers are available in Site A and Site B?
To ensure that all layers are available in both Site A and Site B, the Citrix Engineer should export all layers from ELM Site A to a Windows Share, then import them to Site B. This manual export and import process allows the engineer to move layers between sites efficiently. Other methods, such as using DFSR, are not specifically designed for replicating Citrix App Layering components and could cause issues with layer consistency and integrity.
Go for D https://www.citrix.com/products/citrix-virtual-apps-and-desktops/resources/app-layering-4x-availability-recovery-guide.html
I vote for D as described on https://www.citrix.com/products/citrix-virtual-apps-and-desktops/resources/app-layering-4x-availability-recovery-guide.html
I vote for A. Replication Model In this model, Elastic Layer shares can be replicated using any file-system replication technology. This model can include technologies like DFS-R, Microsoft Storage Replica, Veeam, NAS vendor replication, Zerto, VMware vSphere Replication, and even robocopy. https://docs.citrix.com/en-us/tech-zone/design/reference-architectures/app-layering.html
I also think D as the documentation says that it is currently a manual process to export and import the layers to a second appliance.
I think C. The OS layers/Platform layers en App Layers are stored in de ELM repository which is a local disk inside the linux ELM server, DFS is not possible for these layers. Elastic layers and user layers use an SMB share or can use an DFS share. Because all layers have to move from A to B, answer C is the best answer in my opinion.
A. Reconfigure ELM Site A and ELM Site B to use DFSR for all layers. Explanation: Distributed File System Replication (DFSR) is a Microsoft technology that replicates files between servers and can be used to keep the layers synchronized between the ELM servers in Site A and Site B.
I disagree here with you: https://support.citrix.com/article/CTX227613/app-layering-supporting-dfs-file-shares
https://community.citrix.com/tech-zone/design/reference-architectures/app-layering/
The correct answer for this scenario would be B. Configure layer synchronization directly between ELM Site A and ELM Site B using the Citrix App Layering console. By configuring layer synchronization directly between the ELMs in Site A and Site B using the Citrix App Layering console, the engineer can ensure that all layers are available in both data centers. This approach is more efficient and reliable than exporting and importing the layers manually or using DFSR. Using the Citrix App Layering console to synchronize the layers ensures that any changes made to a layer in Site A will automatically be replicated to Site B, ensuring that the layers are consistent and up-to-date. This approach also allows the engineer to monitor the synchronization process and troubleshoot any issues that may arise.
By configuring layer synchronization directly between ELM Site A and ELM Site B, the Citrix App Layering console will automatically synchronize all layers between the two sites. This ensures that all layers are available in both datacenters, and any changes made to the layers in either site are automatically synchronized to the other site.
https://docs.citrix.com/en-us/citrix-app-layering/4/layer/export-import-layers.html
Answer is D It is also possible to keep two ELM appliances in sync using the layer import/export functionality. This is currently a manual process but layers can be exported to a share and imported to another appliance from that share. Page 222 Student manual v02 Day4-5
Why not C? https://www.citrix.com/products/citrix-virtual-apps-and-desktops/resources/app-layering-4x-availability-recovery-guide.html
I don't think C is the answer. there was no support to export all layer directly between ELM. we should export to SMB share folder path then process the import from other ELM. so, for me D is the best choice but without guarranty