>>Remote resources are less reliable than local.
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>Well, we have no choice. This is a virtual environment and all the data is on a storage device. Then, all the Web servers access the same data, the same as if it would be SQL Server.

The files for each virtual machine in a virtual environment are stored in separate virtual disks (e.g. .vhdx files). Yes, these files may be stored on the same volume on the physical host computer but that doesn't mean they have access to each others' contents.

By default, VMs are separate computers and their resources are isolated from each other. It's possible to set up shared resources via SANs, storage pools etc. but that's not a default configuration, and in many cases those resources aren't available at boot time (support in VMs gets loaded later) so they may not be available when a VM service wants to start.

More conventionally, one VM can be configured to be a file server for the others, just like one physical server in a group of physical servers. Another thing to be wary of in virtualized environments is boot order - if a network share is not available when a VM wants to load a service, it won't load. You may have to specify delayed boot for one VM if it relies on files on a network share provided by another VM.

>>Using launcher-type technology gives the best of both worlds. Check for newer version on network share; if present, copy it to local storage and start it. If the newer version check fails, just use the local version.
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>I see.