oxidecomputer / oxidecomputer/omicron
[sled agent] Disk expungement should unmount filesystem paths
Nobody has claimed this yet.
- Dominant language
- Rust
- Stars
- 572
- Forks
- 97
- Avg merge
- 2d 12h
- Merged PRs (30d)
- 96
Description
Control plane disks have a 1:1 mapping with zpools, which are mounted under `/pool/ext.
Tools like oxlog read from /pool/ext to find logs, and access file system paths.
As implemented today, the sled agent API to configure which disks are active (omicron_physical_disks PUT) does not attempt to unmount filesystems for these paths, when disks are expunged.
As a result, it's possible to have /pool/ext paths lying around after expungement, which are visible to tools reading from the filesystem.
Though the risk for oxlog is relatively low, this behavior is arguably wrong - sled agent should probably take a more active role attempting to remove these filesystem paths from the namespace for expunged disks.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the sled agent API handling the omicron_physical_disks PUT operation and trace the expungement path. Check how /pool/ext filesystem paths are handled when disks are removed; done means expunged disks no longer leave those paths mounted or visible to filesystem-reading tools.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- rust
- Domain
- infrastructure, operating-systems
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 38/100