Getting "Insufficient subnets remaining in the pool" error when running Concourse pipeline

Products

• Concourse for VMware Tanzu

Issue/Introduction

Getting an "Insufficient subnets remaining in the pool" error when running Concourse pipeline, causing the pipeline to fail.

Check the number of Containers used on the Worker nodes. The limit is 256 and the "Insufficient subnets" error can be observed if the limit is reached.

fly  workers
name                 containers platform tags team state  version
0a96dc8a-09c6-4a43-9746-4381d9e05fb6 255     linux   none none running 2.2
537222e6-222c-440c-a0f5-391d6e78f03b 23     linux   none none running 2.2
dfecd51c-6e80-4e93-8879-708ed42d2f27 40     linux   none none running 2.2
e388ef06-5f54-4128-882e-e231bf814135 256     linux   none none running 2.2

Environment

Product Version: Other

Resolution

This is a known issue in pre v5.5.4 versions and the workaround is to recreate Worker VMs.

See further details in the following docs resource: https://docs.pivotal.io/p-concourse/v5/faq/
 

bosh -d CONCOURSE_DEPLOYMENT recreate worker/ID

If the issue persistent and the number of Containers remains high, then further Worker nodes should be added to the deployment.