Index Configuration for AOS/AOSS
Creating Indices with Vector Fields
Semantic Search Index (k-NN enabled)
PUT /my-index
{
"settings": {
"index": {
"knn": true,
"default_pipeline": "my-ingest-pipeline"
}
},
"mappings": {
"properties": {
"text": {"type": "text"},
"embedding": {
"type": "knn_vector",
"dimension": 1024,
"method": {"engine": "faiss", "name": "hnsw", "space_type": "l2"}
}
}
}
}Hybrid Search Index (BM25 + vector)
PUT /my-hybrid-index
{
"settings": {
"index": {"knn": true, "default_pipeline": "hybrid-ingest-pipeline"}
},
"mappings": {
"properties": {
"title": {"type": "text"},
"content": {"type": "text"},
"content_embedding": {
"type": "knn_vector",
"dimension": 1024,
"method": {"engine": "faiss", "name": "hnsw", "space_type": "l2"}
}
}
}
}Ingest Pipeline Configuration
Neural Ingest Pipeline
PUT /_ingest/pipeline/my-ingest-pipeline
{
"processors": [{
"text_embedding": {
"model_id": "<model_id>",
"field_map": {"text": "embedding"}
}
}]
}Search Pipeline Configuration
Hybrid Search Pipeline (normalization + combination)
PUT /_search/pipeline/hybrid-search-pipeline
{
"phase_results_processors": [{
"normalization-processor": {
"normalization": {"technique": "min_max"},
"combination": {"technique": "arithmetic_mean", "parameters": {"weights": [0.3, 0.7]}}
}
}]
}Example Hybrid Query
POST /my-hybrid-index/_search?search_pipeline=hybrid-search-pipeline
{
"query": {
"hybrid": {
"queries": [
{"match": {"content": "search query"}},
{"neural": {"content_embedding": {"query_text": "search query", "model_id": "<model_id>", "k": 10}}}
]
}
}
}AOSS Constraints
- AOSS supports HNSW with Faiss engine only (no IVF, no Lucene engine). NMSLIB is removed in OS 3.x. For the engine matrix, see vector-knn.md.
- AOSS collections are either SEARCH or VECTORSEARCH type — choose VECTORSEARCH for k-NN
- Index names must not start with underscore on AOSS
- AOSS does not support ISM policies — lifecycle is managed at the collection level
Ensure AOSS encryption at rest is enabled before indexing embeddings. Use SigV4 authentication for all operations.
