[DOC] Migration Assistant limitations should be documented in "Is this solution right for you"

[sumobrian]

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• Request a change to existing documentation
• Add new documentation
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Tell us about your request. Provide a summary of the request.

A user should be aware of the MA limitations when assessing whether or not to use the solutions. Here are the limitations that should be documented:

Capture and Replay

• There is an observed 10-30ms impact to indexing traffic during a migration but this may very depending on specific proxy configuration.
• High frequency sequential document updates can result in inconsistent states between source and target if optimistic locking techniques are not employed at the client and/or replay level.
• A single Replay is only supported without additional expert assistance. Live traffic can support a sustained 50MBps (approximately 4TB/day). Github issues with resolution should be referenced so they can be upvoted.
• Clients should specify document IDs rather than relying on Elasticsearch/OpenSearch to generate the IDs because server-side id generation will lead to inconsistent states. Github issues with resolution should be referenced so they can be upvoted.

Reindex-from-Snapshot

• _source must be included (as is the case with all solutions where a reindex is required)