A company is migrating a 50 TB Oracle database to Amazon RDS for Oracle using AWS DMS. The source database is running on-premises and the network link has a bandwidth of 100 Mbps. The migration must complete within 5 days. What is the MOST effective approach to meet the deadline?
Snowball transfers data physically, meeting the 5-day window; DMS handles ongoing changes.
Why this answer
The 50 TB database over a 100 Mbps link would take approximately 48 days for a full load (50 TB * 8 / 100 Mbps / 86400 seconds/day), far exceeding the 5-day deadline. AWS Snowball allows offline transfer of the full database snapshot, bypassing network bandwidth constraints, after which AWS DMS can be used for ongoing change data capture (CDC) to replicate incremental changes. This hybrid approach meets the deadline while ensuring minimal data loss.
Exam trap
The trap here is that candidates assume Direct Connect or DMS online can handle large migrations over slow links, but they fail to calculate the raw transfer time; the question explicitly tests the ability to recognize when offline transfer (Snowball) is the only viable option for multi-terabyte datasets under tight deadlines.
How to eliminate wrong answers
Option A is wrong because provisioning a Direct Connect connection does not inherently increase bandwidth beyond the 100 Mbps link; it only provides a dedicated connection, and even at 10 Gbps, the full load would still take ~11 hours for 50 TB, but the question states the network link is 100 Mbps, implying the bottleneck is the on-premises network capacity, not the connection type. Option C is wrong because using AWS DMS with full load and CDC online over a 100 Mbps link would take ~48 days for the full load alone, far exceeding the 5-day deadline, and CDC cannot start until the full load completes. Option D is wrong because the AWS Schema Conversion Tool (SCT) is used for heterogeneous migrations (e.g., Oracle to PostgreSQL) and does not address the bandwidth limitation; the source and target are both Oracle, so schema conversion is unnecessary, and the data transfer bottleneck remains.