MKE 3.5.7 known issues with available workaround solutions include:
[MKE-9501] Issues with MKE clusters with more than 120 nodes
[MKE-9358] cgroup v2 (unsupported) is enabled in RHEL 9.0 by default
[MKE-8914] Windows Server Core with Containers images incompatible with GCP
[MKE-8814] Mismatched MTU values cause Swarm overlay network issues on GCP
[MKE-9501] Issues with MKE clusters with more than 120 nodes¶
A limitation in MKE 3.5.7 can cause issues in clusters that deploy more than 120 nodes.
If you plan to run a cluster with more than 120 nodes, Mirantis strongly recommends that you upgrade to MKE 3.5.9. If, however, it is imperative that you run one of the affected MKE versions with 121+ nodes, contact Mirantis support to secure a workaround.
[FIELD-5928] MKE cluster agent fails during upgrade¶
During upgrade to MKE 3.5.7, the MKE cluster agent fails in circumstances
wherein a custom NGINX Ingress Controller is deployed in the
Remove the custom NGINX Ingress Controller deployment from
ingress-nginxnamespace prior to upgrade.
Intsall the custom NGINX Ingress Controller on a different namespace:
helm upgrade --install ingress-nginx ingress-nginx \ --repo https://kubernetes.github.io/ingress-nginx \ --namespace ingress-nginx-custom --create-namespace
[MKE-9358] cgroup v2 (unsupported) is enabled in RHEL 9.0 by default¶
As MKE does not support cgroup v2 on Linux platforms, RHEL 9.0 users will be unable to use the software due to cgroup v2 default enablement.
As a workaround, RHEL 9.0 users must disable cgroup v2.
[FIELD-5081] Node Feature Discovery Pods cause crash loop¶
Use of Node Feature Discovery (NFD) Pods can result in a crash loop in Linux systems that are running MCR 20.10.8 and earlier (moby/moby#42836).
As a workaround, update MCR to version 20.10.9 or later.
[MKE-8914] Windows Server Core with Containers images incompatible with GCP¶
The use of Windows ServerCore with Containers images will prevent kubelet from starting up, as these images are not compatible with GCP.
As a workaround, use Windows Server or Windows Server Core images.
[MKE-8814] Mismatched MTU values cause Swarm overlay network issues on GCP¶
Communication between GCP VPCs and Docker networks that use Swarm overlay networks will fail if their MTU values are not manually aligned. By default, the MTU value for GCP VPCs is 1460, while the default MTU value for Docker networks is 1500.
Select from the following options:
Create a new VPC and set the MTU value to 1500.
Set the MTU value of the existing VPC to 1500.
For more information, refer to the GCP official documentation: Change the MTU setting of a VPC network.