What causes "no such block number [%d] in index" in hyperledger/fabric?

Validate blockNum against ledger height before calling

no such block number [%d] in index

Error message

no such block number [%d] in index

What it means

Returned by blockIndex.getBlockLocByBlockNum when a block-number index lookup succeeds at the levelDB layer but returns no value — the requested block number is simply not present in the index (e.g. beyond the ledger height or pruned).

Source

Thrown at common/ledger/blkstorage/blockindex.go:181

		return nil, errors.Errorf("no such block hash [%x] in index", blockHash)
	}
	blkLoc := &fileLocPointer{}
	if err := blkLoc.unmarshal(b); err != nil {
		return nil, err
	}
	return blkLoc, nil
}

func (index *blockIndex) getBlockLocByBlockNum(blockNum uint64) (*fileLocPointer, error) {
	if !index.isAttributeIndexed(IndexableAttrBlockNum) {
		return nil, errors.New("block numbers not maintained in index")
	}
	b, err := index.db.Get(constructBlockNumKey(blockNum))
	if err != nil {
		return nil, err
	}
	if b == nil {
		return nil, errors.Errorf("no such block number [%d] in index", blockNum)
	}
	blkLoc := &fileLocPointer{}
	if err := blkLoc.unmarshal(b); err != nil {
		return nil, err
	}
	return blkLoc, nil
}

func (index *blockIndex) getTxLoc(txID string) (*fileLocPointer, error) {
	v, _, err := index.getTxIDVal(txID)
	if err != nil {
		return nil, err
	}
	txFLP := &fileLocPointer{}
	if err = txFLP.unmarshal(v.TxLocation); err != nil {
		return nil, err
	}
	return txFLP, nil

View on GitHub (pinned to 2736b63f8f)

Solutions

Validate blockNum against ledger height before calling
Retry with backoff when polling for pending commits
Rebuild index if entries below height are missing
Confirm correct channel

Example fix

// before
blk, err := store.RetrieveBlockByNumber(n)
// after
if n >= info.Height { return nil }
blk, err := store.RetrieveBlockByNumber(n)

Defensive patterns

Strategy: retry

Validate before calling

func blockInRange(ledger lgr.PeerLedger, num uint64) (bool, error) {
    bc, err := ledger.GetBlockchainInfo()
    if err != nil { return false, err }
    return num < bc.Height, nil
}

Type guard

func canFetchByNumber(num, height uint64) bool { return num < height }

Try / catch

var blk *common.Block
var err error
for i := 0; i < maxRetries; i++ {
    blk, err = store.RetrieveBlockByNumber(n)
    if err == nil || !strings.Contains(err.Error(), "no such block number") { break }
    time.Sleep(pollInterval) // block may not be committed yet
}

Prevention

Always check GetBlockchainInfo().Height before by-number fetch
Remember block numbers are 0-based: max valid number is Height-1
Use bounded retry/backoff when polling for pending blocks
Confirm channel correctness when numbers come from external sources

When it happens

Trigger: By-number retrieval or index range deletion targeting a block number not in the index: future number, wrong ledger, or missing index entry.

Common situations: Polling for uncommitted blocks, snapshot/truncation-related index gaps, channel mismatch.

Related errors

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/e047497c08d0b7c6. Report an issue: GitHub.