Overview
Ursa Major archive storage uses Google Cloud archive storage classes, chiefly Coldline. These classes are designed for data you need to keep (for funder requirements, reproducibility or backup) but rarely read.
Key rule: reading data back from Coldline carries a retrieval charge, and objects deleted early carry a minimum storage duration charge. Do not use it for data you analyze actively. It suits data you read less than about once a quarter.
Why archive classes
Archive classes cost much less per terabyte to store than Standard storage or provisioned disks. Google publishes current prices on its Cloud Storage pricing page. Under current Ursa Major terms, archive storage may be available without recharge to the lab, within limits. See Cloud archive.
How to archive data
Method A: change a bucket's default storage class
If you have a Standard bucket (gs://my-lab-data) and want new objects stored as archive:
- In the Google Cloud console, open Cloud Storage.
- Click the bucket name.
- Open the Configuration tab.
- Change Default storage class to Coldline.
This affects new objects only. To change existing objects, use a lifecycle rule (Method B).
Method B: lifecycle rule (automatic transition)
Moves objects that have not changed for 30 days. Create lifecycle.json:
{
"rule": [
{
"action": { "type": "SetStorageClass", "storageClass": "COLDLINE" },
"condition": { "age": 30, "matchesStorageClass": ["STANDARD"] }
}
]
}
Apply it:
gcloud storage buckets update gs://my-bucket-name --lifecycle-file=lifecycle.json
Method C: upload directly to archive
gcloud storage cp -r --storage-class=COLDLINE ./my_local_data/ gs://my-archive-bucket/
Recovering a locked project's disks
If a project was locked or suspended because of unattached ("orphaned") disks, Research Computing can help:
- Take a snapshot of the disk.
- Export the snapshot to a Coldline bucket.
- Delete the disk.
The data is then kept in archive storage instead of on a provisioned disk. To request this, contact Research Computing and ask for a "snapshot export to Coldline" for your project.
Before you archive
Check how long you are required to keep the data (records retention), and keep a record of what you archived and where.