Explain Azure Blob Storage access tiers.
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Microsoft Azure conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
Blob Storage offers tiers that trade storage cost against access cost and latency.
- Hot: frequent access, highest storage cost, lowest access cost.
- Cool: infrequent access, minimum 30-day storage, lower storage cost, higher access cost.
- Cold: rarely accessed, minimum 90 days, lower still.
- Archive: offline, minimum 180 days, lowest storage cost, hours to rehydrate before reading.
Set a tier at upload or move blobs later with lifecycle management policies.
{
"rules": [{
"name": "archive-old",
"type": "Lifecycle",
"definition": {
"filters": {"blobTypes": ["blockBlob"], "prefixMatch": ["logs/"]},
"actions": {"baseBlob": {
"tierToCool": {"daysAfterModificationGreaterThan": 30},
"tierToArchive": {"daysAfterModificationGreaterThan": 180}
}}
}
}]
}
Early deletion before the minimum age incurs charges, so model the access pattern before choosing a tier.
Candidate Response Strategy & Interview Tips
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