Increasing System Resources (RAM/CPU) doesn't reflect in OpenShift 4.x cluster when increased from backend in VMware vSphere

Solution Verified - Updated -

Environment

  • Red Hat Openshift Container Platform 4.x
  • VMware vSphere

Issue

  • CPU/memory resources are increased from backend, but doesn't reflect up in OpenShift cluster (Hot Memory/CPU)

Resolution

  • This is a workaround and not recommended by Red Hat . Only option is to re-provision your nodes with additional resources
  • Once CPU/Memory is modified from vSphere and it's visible in Nodes, a restart of kubelet service will reflect updated CPU/Memory status in OCP
# oc debug node/<node-name>
# chroot /host
# systemctl restart kubelet
  • An RFE is already in place to support hot memory/CPU feature. Please open a support case with Red Hat to know the status of RFE at Red Hat Customer Portal

Root Cause

  • By default kubelet holds up configuration in it's memory and it will not reflect changes done from background to nodes unless it's loaded again so even if we add memory/cpu from backend on the fly, it will not display it in OCP cluster(in case node is not rebooted)

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