Overloaded hosts lead to race conditions in pipelines

[tas50]

Describe the problem

We have a single host in the cluster today and multiple jobs are failing with race conditions related the DMGs when verifying builds.

:anka: Cloning macos-omnibus-10.14 to macos-omnibus-10.14-e0fba51a-1f5c-41fa-b7b9-88b2b1aab0b8
Executing . ./.omnibus-buildkite-plugin/test-settings.sh && ./omnibus/omnibus-test.sh in macos-omnibus-10.14-e0fba51a-1f5c-41fa-b7b9-88b2b1aab0b8
Installing unstable chefdk 4.3.7
No receipt for 'com.getchef.pkg.chefdk' found at '/'.
-anka: unmount /private/var/tmp/ankafs.0: Resource busy

See https://buildkite.com/chef/chef-chef-dk-master-omnibus-release/builds/54#e0fba51a-1f5c-41fa-b7b9-88b2b1aab0b8

Software Version

Replication Case

Stacktrace

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Possible Solution

[tduffield]

We don't use this plugin for Omnibus builds. Please re-open against chef/omnibus-buildkite-plugin if this is still an issue.