Mirantis Container Cloud (MCC) becomes part of Mirantis OpenStack for Kubernetes (MOSK)!

Starting with MOSK 25.2, the MOSK documentation set will cover all product layers, including MOSK management (formerly MCC). This means everything you need will be in one place. The separate MCC documentation site will be retired, so please update your bookmarks for continued easy access to the latest content.

StackLight known issues¶

This section lists the StackLight known issues with workarounds for the Mirantis OpenStack for Kubernetes release 21.2.

[13233] Low memory limits for StackLight Helm Controller cause update failure
[12917] prometheus-tf-vrouter-exporter pods fail to start on TF nodes with DPDK

[13233] Low memory limits for StackLight Helm Controller cause update failure¶

Fixed in MOS 21.3

During the MOS cluster update to Cluster release 6.14.0, StackLight Helm Controller containers (controller and/or tiller) may get OOMKilled and cause failure to update.

As a workaround, manually increase the default resource requests and limits for stacklightHelmControllerController and stacklightHelmControllerTiller in the StackLight Helm chart values of the Cluster release resource:

resources:
  stacklightHelmControllerController:
    requests:
      cpu: "250m"
      memory: "128Mi"
    limits:
      cpu: "1000m"
      memory: "512Mi"
  stacklightHelmControllerTiller:
    requests:
      cpu: "250m"
      memory: "128Mi"
    limits:
      cpu: "1000m"
      memory: "2048Mi"

For details about resource limits, see Mirantis Container Cloud Operations Guide: Resource limits.

[12917] prometheus-tf-vrouter-exporter pods fail to start on TF nodes with DPDK¶

Fixed in MOS 21.3

StackLight deploys the prometheus-tf-vrouter-exporter exporter based on the node selector matching the tfvrouter: enabled node label. The Tungsten Fabric nodes with DPDK have the tfvrouter-dpdk: enabled label set instead. Therefore, the prometheus-tf-vrouter-exporter exporter fails to start on these nodes.

Workaround:

Add the tfvrouter-fix: enabled label to every node that contains either the tfvrouter: enabled or the tfvrouter-dpdk: enabled node label.
```
kubectl label node <node_name> tfvrouter-fix=enabled
```
In the Cluster release resource, specify the following nodeSelector definition in the StackLight Helm chart values:
```
nodeSelector:
  component:
    tfVrouterExporter:
        tfvrouter-fix: enabled
```

Once done, prometheus-tf-vrouter-exporter will be deployed to every node with the tfvrouter-fix: enabled label.