diff --git a/docs/concepts/storage/persistent-volumes.md b/docs/concepts/storage/persistent-volumes.md index e45aa5d43612f..bf95508f44c57 100644 --- a/docs/concepts/storage/persistent-volumes.md +++ b/docs/concepts/storage/persistent-volumes.md @@ -118,8 +118,13 @@ For volume plugins that support the Delete reclaim policy, deletion removes both ### Expanding Persistent Volumes Claims -With Kubernetes 1.8, we have added Alpha support for expanding persistent volumes. The current Alpha support was designed to only support volume types -that don't need file system resizing (Currently only glusterfs). +Kubernetes 1.8 added Alpha support for expanding persistent volumes. In v1.9, the following volume types support expanding Persistent volume claims: + +* gcePersistentDisk +* awsElasticBlockStore +* Cinder +* glusterfs +* rbd Administrator can allow expanding persistent volume claims by setting `ExpandPersistentVolumes` feature gate to true. Administrator should also enable [`PersistentVolumeClaimResize` admission plugin](/docs/admin/admission-controllers/#persistentvolumeclaimresize) @@ -147,6 +152,16 @@ by simply editing the claim and requesting bigger size. This in turn will trigg Under no circumstances a new `PersistentVolume` gets created to satisfy the claim. Kubernetes will attempt to resize existing volume to satisfy the claim. +For expanding volumes containing a file system, file system resizing is only performed when a new Pod is started using the `PersistentVolumeClaim` in +ReadWrite mode. In other words, if a volume being expanded is used in a pod or deployment, you will need to delete and recreate the pod for file system +resizing to take place. Also, file system resizing is only supported for following file system types: + +* XFS +* Ext3, Ext4 + +**Note:** Expanding EBS volumes is a time consuming operation. Also, there is a per-volume quota of one modification every 6 hours. +{: .note} + ## Types of Persistent Volumes