Migrating email out of Enterprise Vault is an important milestone.
But it isn’t necessarily the end of the project.
For many organisations, the real objective is to decommission Enterprise Vault completely: removing the infrastructure, licences, operational overhead and support costs associated with a legacy archive.
The danger is switching it off too early.
A successful Enterprise Vault migration therefore needs to answer a more important question than simply “Has the data moved?”
Can we prove that we no longer need the old archive?
Migration and decommissioning are not the same thing
It can be tempting to treat the completion of a migration as the point at which Enterprise Vault can be retired.
In practice, there may still be work to do.
Archived messages need to be accounted for. Exceptions need to be investigated. Enterprise Vault shortcuts may need to be rehydrated or removed. Journal data, leaver archives and other historic information need to be considered.
And the organisation needs confidence that users, compliance teams and eDiscovery processes are no longer dependent on the legacy environment.
That’s why we believe decommissioning should be planned at the beginning of an Enterprise Vault migration, not at the end.
Know what you have before you move it
The first step is discovery.
Before migrating Enterprise Vault to Microsoft 365 or another destination, establish what the archive actually contains.
That includes the number and size of archives, users and former users, journal archives, retention requirements and any data that may no longer need to be retained.
This creates a baseline against which the completed migration can eventually be measured.
Without that baseline, answering “Did everything move?” becomes considerably harder.
Make migration validation part of the project
Moving millions of historic messages creates plenty of opportunities for exceptions.
Individual items may be corrupt. Data may not meet the requirements of the destination. An archive may contain unexpected content. Some information may deliberately be excluded from the migration.
None of those things necessarily means the migration has failed.
What matters is being able to identify, explain and account for the difference between the source and destination.
A successful migration isn’t simply one where lots of data appears in Microsoft 365. It is one where the outcome can be demonstrated.
That means reconciliation, exception reporting and validation should be built into the migration process.
Don’t forget Enterprise Vault shortcuts
Shortcuts are another important part of an Enterprise Vault exit.
Users may have thousands of shortcuts in their mailboxes representing messages held within Enterprise Vault.
Those need to be considered as part of the migration and decommissioning strategy. Depending on the chosen approach, archived messages may need to be rehydrated and shortcuts processed so that users aren’t left with links pointing towards an archive that no longer exists.
Leaving this until after the migration can make decommissioning unnecessarily difficult.
Check who still depends on the archive
Enterprise Vault may also be serving purposes beyond everyday access to old email.
Before decommissioning, organisations should consider requirements around retention, legal hold, compliance, eDiscovery and historic journal data.
The question isn’t simply whether users can find their old messages.
It’s whether every legitimate dependency on Enterprise Vault has either been migrated, replaced or deliberately retired.
Create a clear decommissioning decision
The final stage should therefore be an explicit decision rather than somebody simply switching off a server.
Can you account for the information that was in Enterprise Vault?
Has the required data been successfully migrated?
Have exceptions been resolved or accepted?
Are shortcuts dealt with?
Can users access the information they need?
Are retention, compliance and eDiscovery requirements covered by the new environment?
If the answer to those questions can be demonstrated, you have a much stronger basis for retiring the legacy platform.
Make the exit part of the migration
Enterprise Vault migrations are often initiated because organisations want to modernise their email environment, move to Microsoft 365 or reduce the cost and complexity of maintaining legacy archive technology.
But those benefits aren’t fully realised while the old platform is still running.
At Ultimate Migrator, we help organisations discover, migrate and validate historic email data, providing the evidence needed to move towards the eventual decommissioning of legacy archive environments.
Our experience includes complex Enterprise Vault migrations at significant scale, including the migration of historic email for approximately 180,000 NHS Wales users.
If you’re planning an Enterprise Vault migration, we’d recommend asking one question at the outset:
What will we need to prove before we’re comfortable switching it off?