/amazon-opensearch-service

Migration Assessment Report — {{ fingerprint.source_engine }} {{ fingerprint.version | default:'(version unknown)' }} → Amazon OpenSearch

Date: {{ date }}
Skill: amazon-opensearch-service v{{ skill_version }}
Persona: {{ persona }}
Source: {{ fingerprint.source_engine | default:'unknown' }} {{ fingerprint.version | default:'(version not provided)' }}
Target: {{ migration_path.decision_inputs.target | default:'managed' }}
Recommended migration tool: {{ migration_path.recommended }}

Executive Summary

This assessment evaluates a {{ fingerprint.source_engine }} workload for migration to Amazon OpenSearch {{ migration_path.decision_inputs.target | default:'Service' }} in {{ sizing.region | default:'us-east-1' }}.

Key findings

• Migration readiness score: {{ readiness.overall_score }}/100 ({{ readiness.tier }})
• Recommended migration tool: {{ migration_path.recommended }}
• Sizing: see Sizing section below; plug values into https://calculator.aws for monthly cost
• Confidence: see Risks section below

A green tier (≥80) means you SHOULD proceed with the planned migration; yellow tier (60–79) means you SHOULD run a PoC + spike on the lowest-scoring dimension; red tier (<60) means you MUST NOT commit until the risk-blocker findings are reduced because the readiness score is below the safe-migration threshold.

Source

Source artifacts collected

{{ fingerprint.files_provided | json }}

{{ fingerprint | json }}

Target

Recommended deployment: {{ migration_path.decision_inputs.target | default:'managed' }}

{% if sizing.compute.data_node_instance %}- Compute: {{ sizing.compute.data_node_count }}× {{ sizing.compute.data_node_instance }}

• Cluster managers: {{ sizing.compute.cluster_manager_count }}× {{ sizing.compute.cluster_manager_instance }}
• Storage: {{ sizing.storage.gb_per_node }} GB per node ({{ sizing.storage.type }})
• Region: {{ sizing.region }} {% endif %}{% if sizing.compute.indexing_ocu_min %}- Indexing OCUs (minimum): {{ sizing.compute.indexing_ocu_min }}
• Search OCUs (minimum): {{ sizing.compute.search_ocu_min }}
• Redundancy: {{ sizing.compute.redundancy }}
• Storage: {{ sizing.storage.gb }} GB ({{ sizing.storage.type }})
• Region: {{ sizing.region }} {% endif %}

For target-shape reasoning (managed vs Serverless NextGen) see assessment-workflow.md. Sizing math: sizing.md.

Migration Path

Recommended tool: {{ migration_path.recommended }}

Ranked options

| Option | Score | Pros | Cons |
|---|---|---|---|
{% for r in migration_path.ranked_options %}| **{{ r.option }}** | {{ r.score }} | {{ r.pros | bullets }} | {{ r.cons | bullets }} |
{% endfor %}

Decision inputs

{{ migration_path.decision_inputs | json }}

For full per-component strategy tables (Historical Data Migration / Live Traffic Migration / Application Code Rewrite) and the always-true source-engine rules, see assessment-workflow.md.

Sizing — for the AWS Pricing Calculator

Region: {{ sizing.region | default:'us-east-1' }} · Report date: {{ date }}

{{ sizing | json }}

How to compute monthly cost

This skill produces sizing inputs only. You MUST plug them into the AWS Pricing Calculator at https://calculator.aws: add an estimate, pick Amazon OpenSearch Service or Serverless NextGen, enter the compute / storage / OCU values from the sizing block, and apply RI / Savings Plan / EDP discounts. You MUST add a separate calculator entry for migration tooling (Migration Assistant for Amazon OpenSearch Service EKS infra, OSI OCUs, S3 snapshot storage) for the one-time cost.

Readiness

Overall score: {{ readiness.overall_score }}/100 — Tier: {{ readiness.tier }}

Per-dimension breakdown

Tier guidance

• GREEN (≥80): You MUST proceed and surface top items to flag (split across Migration specifics and Risks/blockers).
• YELLOW (60–79): You MUST run a PoC + spike on the weakest dimension.
• RED (<60): You MUST NOT commit because the readiness score is below the safe-migration threshold. Revisit the weakest dimension first.

Risks & migration specifics

Two-table section. See assessment-gotchas.md for general anti-patterns and compatibility-rubric.md for the canonical Severity + Lane vocabulary.

For the full per-finding register use the engine-specific gap register: solr-gap-register.md for Solr sources, elasticsearch-gap-register.md for Elasticsearch / OpenSearch sources.

Migration specifics

Items the migration plan already handles via a documented remediation. The auto-seeded rows below have a Workaround field by definition — every row here is a migration specific. Frame these as "this is how the migration handles X".

| ID | Severity | Description | Remediation (handled by the path) |
|---|---|---|---|
{% if fingerprint.source_engine == 'solr' %}{% if fingerprint.summary.dih_used %}| SOLR_DIH | HIGH | Solr Data Import Handler (DIH) was removed in Solr 9.0 | Migrate ETL to OpenSearch Ingestion (OSI), Data Prepper, AWS DMS, or Logstash |
{% endif %}{% if fingerprint.summary.velocity_response_writer %}| SOLR_VELOCITY | HIGH | Velocity Response Writer is deprecated/removed in modern Solr | Move templating into the application layer |
{% endif %}{% if fingerprint.summary.xslt_response_writer %}| SOLR_XSLT | HIGH | XSLT Response Writer has no OpenSearch equivalent | Move templating into the application layer |
{% endif %}{% endif %}{% if fingerprint.source_engine == 'elasticsearch' %}{% if fingerprint.summary.ilm_used %}| ES_ILM | HIGH | ES Index Lifecycle Management (ILM); policy JSON does not import as ISM | Rewrite policies as ISM and re-attach (see source-elasticsearch.md) |
{% endif %}{% if fingerprint.summary.watcher_used %}| ES_WATCHER | HIGH | X-Pack Watcher has no direct equivalent | Rebuild as OpenSearch Alerting monitors |
{% endif %}{% if fingerprint.summary.runtime_fields_used %}| ES_RUNTIME_FIELDS | HIGH | ES runtime (schema-on-read) fields have no OpenSearch equivalent | Pre-compute at ingest or use scripted_field; reindex |
{% endif %}{% if fingerprint.summary.source_disabled %}| ES_SOURCE_FALSE | HIGH | `_source: {enabled:false}` index — Migration Assistant for Amazon OpenSearch Service Historical Data Migration recovers documents (nugget #22) | Use Migration Assistant for Amazon OpenSearch Service Historical Data Migration; re-enable `_source` on target |
{% endif %}{% endif %}| *Add per-finding rows here* | | | |

Risks / blockers

Items that genuinely constrain the migration: no known fix, capacity-plan implications, irreversible target choices, or customer-action dependencies that can fail late. These deduct from the Compatibility readiness weight per readiness-rubric.md.

| ID | Severity | Description | What's at stake |
|---|---|---|---|
{% if fingerprint.source_engine == 'solr' and fingerprint.summary.custom_lib_count %}| SOLR_CUSTOM_PLUGIN | HIGH/BLOCKING | Custom plugin JARs ({{ fingerprint.summary.custom_lib_count }} `<lib>` directives) must port to the OpenSearch plugin API | Not supported on Serverless NextGen — constrains target choice; needs a plugin port plan or RFC |
{% endif %}{% if fingerprint.source_engine == 'elasticsearch' and fingerprint.summary.post_fork %}| ES_POST_FORK | HIGH | Source is ES ≥ 7.11 (ELv2/SSPL) — Snapshot/Restore to AOS is NOT supported (nugget #21) | Tool-choice lockout: must use Migration Assistant for Amazon OpenSearch Service Historical Data Migration (any volume) or `_reindex` from remote; flag legal review |
{% endif %}| *Add per-finding rows here* | | | |

What I assumed (defaults applied for UNKNOWN inputs)

• Pricing: not estimated — the customer plugs sizing into https://calculator.aws for an authoritative figure
• Default replicas: 1 (per assumptions.md)
• Default refresh_interval: 30s (not 1s — Skill IP: operational guidance for prod, verify against bp.html in knowledge-retrieval.md)
• Engineering hours estimate: Skill IP, derive from readiness tier
• Defaulted to managed Multi-AZ-with-Standby topology unless Serverless NextGen was clearly indicated
• For Migration Assistant for Amazon OpenSearch Service cost projections, follow the AWS Solutions cost guide cited in knowledge-retrieval.md (Migration Assistant for Amazon OpenSearch Service section)

Citations

The single canonical provenance record for this assessment (resolved in the Step 8 batched pass — no inline per-claim citations needed). For the canonical retrieval recipe (every URL the skill ever cites, topic → tool → URL, with browser/CLI fallbacks when the AWS MCP server is not available), see knowledge-retrieval.md. You MUST list, with retrieval timestamps, the version-volatile claims you actually verified — typically including:

• The specific best-practice page used for the sizing math (Amazon OpenSearch Service (managed) section)
• The AWS upgrade-path doc for any upgrade-path claim (Amazon OpenSearch Service (managed) section)
• The Migration Assistant for Amazon OpenSearch Service doc (AWS) and project doc when Migration Assistant for Amazon OpenSearch Service is the recommendation (Migration Assistant for Amazon OpenSearch Service section)
• The Serverless NextGen comparison and general reference docs for any Serverless NextGen claim (Amazon OpenSearch Serverless NextGen section)
• The AWS Pricing Calculator URL — https://calculator.aws — for the cost handoff

Generated by amazon-opensearch-service v{{ skill_version }} on {{ date }}.