Description of problem: When OCS was deployed with arbiter mode enable add capacity is increasing the count by "2" Version-Release number of selected component (if applicable): OCP:- 4.7.0-0.nightly-2021-01-19-095812 OCS:- ocs-operator.v4.7.0-238.ci How reproducible: Always Steps to Reproduce: 1. Deploy OCP 4.7 over VMware 2. Deploy OCS 4.7 with arbiter mode enable 3. Perform Add Capacity Actual results: We have seen that UI increase count by 2 and new "8" osd are getting created #Snippet from storagecluster storageDeviceSets: - config: {} count: 3 dataPVCTemplate: metadata: {} spec: accessModes: - ReadWriteOnce resources: requests: storage: "1" storageClassName: localblock volumeMode: Block status: {} name: ocs-deviceset-localblock placement: {} preparePlacement: {} replica: 4 resources: {} version: 4.7.0 Note:- Add Capacity was only perform Once Expected results: UI should increase the count by "1" Additional info: #### Before Add Capacity (Snippet from Storage cluster) #### storageDeviceSets: - config: {} count: 1 dataPVCTemplate: metadata: {} spec: accessModes: - ReadWriteOnce resources: requests: storage: "1" storageClassName: localblock volumeMode: Block status: {} name: ocs-deviceset-localblock placement: {} preparePlacement: {} replica: 4 resources: {} #### After Add Capacity (Snippet from Storage cluster) #### storageDeviceSets: - config: {} count: 3 dataPVCTemplate: metadata: {} spec: accessModes: - ReadWriteOnce resources: requests: storage: "1" storageClassName: localblock volumeMode: Block status: {} name: ocs-deviceset-localblock placement: {} preparePlacement: {} replica: 4 resources: {}
> Expected results: > UI should increase the count by "1" Based on my understanding of arbiter feature, expanding by one is not a valid operation in a stretch cluster. When I add new OSD into a data zone A, I also have to add new OSD into data zone B, making sure the new OSDs have the same size.
(In reply to Martin Bukatovic from comment #3) > > Expected results: > > UI should increase the count by "1" > > Based on my understanding of arbiter feature, expanding by one is not a > valid operation in a stretch cluster. When I add new OSD into a data zone A, > I also have to add new OSD into data zone B, making sure the new OSDs have > the same size. Correct, we have two Data Zones and we can expand by 2 nodes one for each data zone. As we use replica4 , expanding by 4 OSDs make sense as it will make sure we two new OSDs in each data zone. 8 OSDS is a bug. It is possible to expand by 2 with one OSD per zone but it will make the usable capacity calculation more complicated. For the UI in OCS 4.7 we will go with expanding 4 OSDs each time.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (Moderate: OpenShift Container Platform 4.7.0 security, bug fix, and enhancement update), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHSA-2020:5633