Check Blob lifecycle rules before changing access tiers

Why this is worth a look

Skipping this review can return a restored blob to Archive when its creation, last-modified or last-access time meets a rule threshold. Lifecycle policies are free, but their Set Blob Tier calls incur standard operation charges. Moving data out of Archive also uses read-operation, retrieval-per-GB and, before 180 days, prorated early-deletion meters.

Use this checklist in Azure Cost Analysis and with policy and blob details supplied by an authorized storage owner. Scope it to one account and the target blobs. Record results only and do not change resources.

1. Open Azure portal > Cost Management + Billing > Cost management > Cost analysis. Select the subscription in Scope. Add filter > Service name > Storage, then add a filter for the target storage account. Record the scope, displayed date range and current costs.
2. Separate storage capacity from move costs. Record Data Stored in GB/month; Azure bills this line in GB calculated as binary GB (GiB). Treat the current cost view as a baseline, not a tier-change estimate.
3. Read the account's lifecycle policy JSON supplied by the storage owner. Record matching actions, time conditions, path prefixes and blob-index tags. Prefix paths start with the container name. Multiple filters in one rule use logical AND.
4. For a restore from Archive, compare each target blob's creation, last-modified and last-access times with the matching archive rule. Record whether its tierToArchive action includes daysAfterLastTierChangeGreaterThan. Flag a rule that could archive the restored blobs again.
5. For a Set Blob Tier move out of Archive, record the operation count, GB to retrieve and time already spent in Archive. Include Archive read-operation charges, retrieval per GB and a prorated early-deletion fee for data moved before 180 days.
6. Confirm the planned tier change is for Block Blobs outside premium block blob accounts. Do not plan to use lifecycle management to restore Archive blobs to an online tier. Record any required policy review for the storage owner; make no changes during this review.

How to confirm it

1. 01

   Record the cost baseline

   Run the cost-view portion of the checklist for one account. Keep the subscription, account and displayed date range with the result so finance and engineering compare the same scope and period.

2. 02

   Find rules that could undo the move

   Compare the target blobs with the policy's filters and time conditions. For an Archive restore, flag any rule that could send them back to Archive and ask the storage owner to review daysAfterLastTierChangeGreaterThan or a location outside that policy.

3. 03

   Check move charges and support

   Record the Archive retrieval volume, operation count and time in Archive before approving a restore. Confirm the account and blob types support tiering. Stop if the plan relies on lifecycle management to restore archived data.

4. 04

   Allow for policy processing

   Wait for any separately approved policy update to take effect before relying on it. Activation can take up to 24 hours, and processing can take longer depending on account size and operations. Do not treat 24 hours as a completion deadline.

Primary sources