Cloud-based Archive Migrations

This will vary depending on your chosen hosted archive service.

For example, Transvault transfers data directly over the network to Microsoft Office 365 using the EWS protocol.

For extremely large data transfers, or where there is no existing API, a typical strategy is to store data on removable media in a neutral file format such as PST or EML files. In this case TransVault can be configured to package and name the exported data according to the conventions stipulated by the hosted vendor.

The removable media would then be shipped to the hosted service provider for ingestion.

To ensure peace of mind, Transvault creates a full report of exactly what data has been extracted from your system to be handed to the service provider.  This further acts as evidence of due diligence in support of future eDiscovery requests.

Mimecast does not as yet publish a public API for large scale data extraction.

You can extract a given mailbox or set of data from Mimecast by using Administrator rights to export the results of an eDiscovery search to PST or EML files. Find our more about exporting message data in Mimecast and more about our Mimecast migration service.

This, however, is a very lengthy and manually intensive approach that is not suitable for large volumes.

Another approach is to request a bulk-export of emails.  This data will typically presented in a single-instanced stream of emails in PST or Zipped EML files.

The challenge with this is that your emails will not exported according to individual user mailboxes and and does not preserve any folder structure.

Transvault is able to take this pool of emails and reconstruct it into separate user mailboxes.  It can also create a new email folder structure based on meta data such as ‘Sender’ and  ‘Date’ to give users the most meaningful way to navigate their migrated email records.

At the same time you can output data in the required format for ingestion into your new target cloud service, be it Office 365 or elsewhere.

Many hosted archive vendors will ingest your data from PST files, but don’t underestimate what is involved in
manually exporting and preparing your legacy data into this format.

Although many archive systems have some kind of ‘export to PST files’ function, there are common problems
associated with such tools, including:

• They’re labor-intensive – While fine for exporting 1 or 2 mailboxes, native export tools are not
  suitable for bulk movement of data out your archive. There’s no batching capability or automation and
  you will need to dedicate a member of staff to constantly monitor the entire process which may take
  many months.
• It’s slow – ‘Native’ extraction tools are typically single-threaded tools. We suggest you time the
  extraction of a single, average-sized mailbox.
• There’s no reporting – There is no proof or audit log of what data has been extracted out of your
  system.
• There’s no error handling – If a mailbox extraction fails owing to a corrupted email, the extraction will
  stop with no indication of which item was corrupted and no ability to pick up where the extraction left
  off.
• Important meta-data is lost – There is no support for migrating BCC’d and distribution list recipients
  from journal archives, no protection of retention dates, no ability to re-write addresses, etc.
• Large PST files are prone to corruption – This creates problems for organizations trying to extract the
  contents of very large mailbox archives or Journal mailbox archives.
• Lack of flexibility – Native extractions typically extract an entire mailbox, offering no granularity, such
  as extracting only the last 5 year’s worth of data.

By comparison Transvault offers automated extraction, with full error-logging, unattended operation,
reporting and unparalleled flexibility and data fidelity. It can also be configured to package PSTs in the
recommended format, label them with the correct header information, split out large mailboxes/journal
archives into multiple linked PSTs, etc.

A Transvault-lead migration service can also save you money: A recent costing exercise based on hiring a temp
(at $18 per hour) to manually extract data to PST files, and an average migration time of 3 hours indicated a
cost of around $54 per mailbox (including manual auditing, checking etc). Bear in mind this is just ‘half’ of the
process as the contents of PST files then need to be ingested into the target archive. This means manual
migration costs can reach over $100 per mailbox.

Migration speeds have been measured in excess of 2TB a day.

As well as running multiple threads on a single server and across single mailboxes, multiple Transvault servers can be configured to operate in parallel and:

• Extract from multiple mailboxes and multiple file stores at once from your current archiving environment
• Migrate to many mailboxes simultaneously
• Have multiple migration tasks operating in parallel on individual extra large mailboxes

The transfer of emails to Exchange uses MAPI for optimum speed.

Note, however, that achieving best performance is dependent on many factors such as:

• Available network bandwidth
• Loading on the legacy email archive and your Exchange servers
• The speed of the storage subsystem on which the legacy archive sits

Your chosen archive migration partner can establish a proof of concept (POC) to establish likely throughput rates in your specific environment.

Depending on your chosen cloud vendors, options for extracting data out of an existing cloud service can often
be limited, time-consuming and costly.

For example, if you wanted to extract a given mailbox or set of data from Mimecast, one option is to use
Administrator rights to export the results of an eDiscovery search to PST or EML files.

This, however, is a very lengthy and manually intensive approach that is not suitable for large volumes.

Another approach is to request a bulk-export of archived data from your cloud vendor. This data will typically
be presented in a single-instanced stream of emails in PST or Zipped EML files. The challenge with this is that your emails will not exported according to individual user mailboxes and the original folder structure is lost.

Transvault is able to take this pool of emails and reconstruct it into separate user mailboxes. It can also create
a new email folder structure based on meta data such as ‘Sender’ and ‘Date’ to give users the most meaningful
way to navigate their migrated email records. At the same time you can output data in the required format for ingestion into your new target cloud service.

Note that Microsoft Office 365 offers a great deal more flexibility and capability for moving your archives and
for maintaining the folder structure of an individual’s mailboxes.