Bug 1935347

Summary: kube-storage-version-migrator is unschedulable if no worker nodes are available
Product: OpenShift Container Platform Reporter: Christoph Blecker <cblecker>
Component: kube-storage-version-migratorAssignee: W. Trevor King <wking>
Status: CLOSED DUPLICATE QA Contact: Ke Wang <kewang>
Severity: low Docs Contact:
Priority: low    
Version: 4.7CC: aos-bugs, sanchezl, wking
Target Milestone: ---Keywords: Reopened, ServiceDeliveryImpact
Target Release: 4.8.0   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Cause: kube-storage-version-migrator did not tolerate 'master' nodes and provided no mechanism to configure custom tolerations. Consequence: When compute was scaled to zero, kube-storage-version-migrator was unschedulable. Fix: kube-storage-version-migrator now tolerates 'master'. Result: As long as there is space somewhere in the cluster, kube-storage-version-migrator will be able to run.
 Story Points: ---
Clone Of: Environment:
Last Closed: 2021-03-15 23:46:16 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Christoph Blecker 2021-03-04 16:44:07 UTC 
Description of problem:
The kube-storage-version-migrator migrator deployment is unschedulable if there are no worker nodes available, causing the cluster operator to degrade.

This can cause problems in managed OpenShift environments where all control plane components should be able to be scheduled even if the worker pool is scaled to zero.

Version-Release number of selected component (if applicable):


How reproducible:
Consistent


Steps to Reproduce:
1. Scale worker pool to zero

Actual results:
The migrator workload pod is in a Pending state even thought the operator pod itself will schedule onto the control plane nodes. The cluster operator will degrade.

Expected results:
The migrator pod would reschedule onto the control plane nodes.


Additional info:
Comment 1 W. Trevor King 2021-03-15 22:28:03 UTC 

*** This bug has been marked as a duplicate of bug 1881938 ***
Comment 2 W. Trevor King 2021-03-15 23:46:16 UTC 
Go away bot ;).

*** This bug has been marked as a duplicate of bug 1881938 ***