Aerospike asrestore record-count verification after namespace restore

Answering the Question

After running asrestore, a single record‑count comparison with asinfo or asadm is a *necessary* sanity check, but it is not *sufficient* to prove that the restored data matches the source. The recommended approach is a two‑step verification: first confirm the namespace’s record count matches the backup header, then perform primary‑key spot checks against a known key set. The Community and Enterprise editions expose the same nsstats command; the only edition‑specific difference is that Enterprise guarantees stronger consistency in multi‑node clusters, but this does not affect the restore itself. The key flags that influence post‑restore validation are -o (overwrite) and -i (incremental). Using -o guarantees a clean namespace, preventing accidental merges with pre‑existing data.

Why Count Alone Is Insufficient

• Missing or corrupted records can still satisfy the total count.
• Duplicate keys inserted after the backup may inflate the count without changing logical data.
• Compression or pruning options during backup can alter the header’s record count, making a direct comparison misleading.

Recommended Verification Flow

1. Record the pre‑restore state (optional). If the target namespace may contain data, capture its current count:

   asinfo -c "nsstats" | grep <namespace> | awk '{print $2}'
   

2. Run the restore with overwrite. This guarantees no stale data remains:

   asrestore -n <namespace> -o <backup-dir>
   

3. Verify the post‑restore count. Capture the count again:

   asinfo -c "nsstats" | grep <namespace> | awk '{print $2}'
   

4. Cross‑check with the backup header. The header file (e.g., backup/backup.header) contains the original record count. Ensure the post‑restore count equals this value.
5. Perform primary‑key spot checks. Select 10–20 keys from the backup (either by reading the header or sampling the backup files). For each key, retrieve the record from the restored namespace and compare values:

   asinfo -c "get" -key <key>
   

   If any mismatch appears, investigate further.
6. Optional: Compute a checksum of a sample set. For high‑assurance scenarios, hash the values of the spot‑checked keys and compare against a checksum computed on the source system.

Edition‑Specific Considerations

• The -o flag behaves identically in Community and Enterprise editions.
• Enterprise’s stronger consistency guarantees affect read/write operations during the restore but do not change the verification steps.
• If using Enterprise’s asrestore -i for incremental restores, you must also verify that the incremental delta files match the target namespace’s current state before applying them.

Missing Diagnostic Detail

To tailor the verification precisely, it would help to know whether the target namespace was empty before the restore. If it was not empty, you should confirm that the -o flag was used; otherwise, the count comparison might hide unintended merges.