disk check – fix excluded_disks and excluded_filesystems

[tristanpemble]

What does this PR do?

fixes #12676 so that the config values are properly read.

Motivation

excluded_disks and excluded_filesystems are ignored in the disk check. this makes it impossible to shut the datadog-agent up when you're running it alongside a Docker daemon:

datadog-agent[741351]: {"agent":"core","time":"2022-10-19 21:37:45 UTC","level":"WARN","file":"pkg/collector/corechecks/system/disk/disk_nix.go","line":"69","func":"collectPartitionMetrics","msg":"Unable to get disk metrics of /run/docker/netns/dc7cd87fb085 mount point: permission denied"}
datadog-agent[741351]: {"agent":"core","time":"2022-10-19 21:37:45 UTC","level":"WARN","file":"pkg/collector/corechecks/system/disk/disk_nix.go","line":"69","func":"collectPartitionMetrics","msg":"Unable to get disk metrics of /var/lib/docker/overlay2/5e665e6efd833cf145533eae8d17c8133bc418a46e14fe362a665698b6530312/merged mount point: permission denied"}
datadog-agent[741351]: {"agent":"core","time":"2022-10-19 21:38:00 UTC","level":"WARN","file":"pkg/collector/corechecks/system/disk/disk_nix.go","line":"69","func":"collectPartitionMetrics","msg":"Unable to get disk metrics of /var/lib/docker/overlay2/0aa531af6b93c0ee052da4819f6fb09109bfae5d2033b5c04020e00f30ff05c8/merged mount point: permission denied"}
datadog-agent[741351]: {"agent":"core","time":"2022-10-19 21:38:00 UTC","level":"WARN","file":"pkg/collector/corechecks/system/disk/disk_nix.go","line":"69","func":"collectPartitionMetrics","msg":"Unable to get disk metrics of /var/lib/docker/overlay2/b5e42024c90dcc6628ab2efd479cd0d550643a94ce1b4e859b1838156625496a/merged mount point: permission denied"}
datadog-agent[741351]: {"agent":"core","time":"2022-10-19 21:38:00 UTC","level":"WARN","file":"pkg/collector/corechecks/system/disk/disk_nix.go","line":"69","func":"collectPartitionMetrics","msg":"Unable to get disk metrics of /var/lib/docker/overlay2/afddbb4089d7507c927e3318bda3eb81d5cd29dee4b284c0a5e30d2eb3cfbb41/merged mount point: permission denied"}

Additional Notes

casting []interface{} to []string does not work; so this conditional fails silently. the result is that these config values do not work.

Possible Drawbacks / Trade-offs

Describe how to test/QA your changes

Reviewer's Checklist

• If known, an appropriate milestone has been selected; otherwise the Triage milestone is set.
• Use the major_change label if your change either has a major impact on the code base, is impacting multiple teams or is changing important well-established internals of the Agent. This label will be use during QA to make sure each team pay extra attention to the changed behavior. For any customer facing change use a releasenote.
• A release note has been added or the changelog/no-changelog label has been applied.
• Changed code has automated tests for its functionality.
• Adequate QA/testing plan information is provided if the qa/skip-qa label is not applied.
• At least one team/.. label has been applied, indicating the team(s) that should QA this change.
• If applicable, docs team has been notified or an issue has been opened on the documentation repo.
• If applicable, the need-change/operator and need-change/helm labels have been applied.
• If applicable, the k8s/<min-version> label, indicating the lowest Kubernetes version compatible with this feature.
• If applicable, the config template has been updated.

[bits-bot]

All committers have signed the CLA.

[mikecook]

Bump for reviewer

[amenasria]

👋 Hey @tristanpemble, sorry for the late reply. Thanks a lot for your PR !

Lot of work right now, our team will review it ASAP.

Could you please provide your /etc/datadog-agent/conf.d/disk.d/conf.yaml config file (not the one in #12676 but the one before your blacklists configuration tests) ? That would help us faster review your PR !

[tristanpemble]

👋 Hey @tristanpemble, sorry for the late reply. Thanks a lot for your PR !

Lot of work right now, our team will review it ASAP.

Could you please provide your /etc/datadog-agent/conf.d/disk.d/conf.yaml config file (not the one in #12676 but the one before your blacklists configuration tests) ? That would help us faster review your PR !

unfortunately, I have since left the company I was at when I filed this PR, so I cannot do this

[RoseSecurity]

Any updates on this?