Cloud Infrastructure · Cluster
Cloud Migration
Assessment, cutover, and rollback.
- 01 Dependency Discovery from Observed Traffic and Configuration Graphs Why declared configuration undercounts a system's real dependencies, what a flow record can prove, and how sampling and timeouts corrupt an inferred call graph.
- 02 The Cutover Boundary of a Workload and Why It Is Never One Process How to decide which processes, data stores, and identities must move as one unit, what breaks when a boundary is drawn too small, and the cost of drawing it too large.
- 03 Bulk Copy and Change Stream: Making an Online Copy Consistent Why a snapshot must be pinned to a stream position before the copy begins, how the catch-up phase terminates, and where replication lag turns into an unbounded delay.
- 04 DNS TTL, Resolver Caches, and the Real Duration of a Cutover How negative caching, recursive resolvers, and connection reuse stretch a five-minute TTL into hours of split traffic, and what actually bounds the redirect window.
- 05 Shadow Traffic and Differential Comparison Before a Cutover How mirrored requests expose behavioural differences between two implementations, why response bodies rarely compare cleanly, and what a comparison harness must normalise.
- 06 Rollback as a Question of Write Reversibility Why reverting traffic is easy and reverting state is not, how dual-write and tombstones change the rollback budget, and when a cutover becomes one-way.
- 07 Moving Workloads with Overlapping Private Address Space Why two RFC 1918 networks that both use 10.0.0.0/8 cannot be joined by routing alone, how translation state makes the link fragile, and where addresses embedded in payloads defeat it.
- 08 Sequencing a Cutover Against a Dependency Graph Why the ordering of moves is constrained by who calls whom, how to find a valid sequence, and what happens when the graph contains a cycle.
- 09 Post-Cutover Reconciliation and Drift Detection How to prove that a destination holds the same state as its source after the switch, why checksums over large tables lie, and how to detect divergence that appears later.
- 10 Decommissioning a Source System: Proving Quiescence Why an idle-looking system is not an unused one, how to measure the absence of traffic, and the sequence that ends with a restore test rather than a shutdown.