Hi again,
I'm not sure how Supported it is ... but if I remember correctly the chunk size *can* be changed from 10 Mb, upwards, or downwards - push beg and holler your Symantec person to get you the details. I believe there is a good article on the forums that explains the full process of client side PST migration, it's not perfect, I will give you that, but it has as one of it's main purposes "remote" clients as a direct-goal. What happens in general terms is the PST is split up in to 10 Mb chunks, and then at the end any additional data that was added to the PST is also then uploaded. So the PST can be in use, during the migration.
Proactive caching, aka trawling, takes place against the Outlook OST file. The idea being that "stuff" is added to Vault Cache that is "soon to be archived", so that when it's actually archived, it doesn't then have to be downloaded from the EV server to the Vaul Cache. The item that is trawled, or pre-emptively cached, or proactively cached (depending on your terminology) is the full item that existed in your OST file. Like I say it's to stop the roundtrip download from the EV server when it is actually archived.
Proactive caching, doesn't touch PST files.
If your users drag and drop stacks of data into Virtual Vault from PSTs then that will trigger a PUSH of that data up to the EV server. You can configure limits in your policy.
Regarding the final question ... I have no idea what the Puredisk-assisted (or external HD-assisted) methods are. I've not heard of them before. With regards to external HD, if you can "somehow" get a stack of PSTs from each user copied to an external hard drive, transported to your EV data centre, and imported via the VAC or by search/locate/migrate, then that will work... I just think it's a *very* difficult job to get the PSTs on to the external hard drives in the first place.
The options are all yours.. pro's and con's, and really this is the land of Symantec Consultancy (or a 3rd party)... I don't think there is a quick way to give a definite answer of "yes this way will work", but hopefully we've discussed some useful ideas at least? (Keep the ideas/comments/questioins coming too, if you need more input)
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