Kubernetes pv uid. For example, consider a Service that creates EndpointSlice objects. Familiarity with volumes and persistent volumes is suggested. Security Enhanced Linux (SELinux): Objects are assigned security labels. Fundamentals PV is a storage resource that is controlled by the cluster admin. claimRef. svc. By employing the correct VolumeMount practices with user and group configurations, you ensure both data security and accessibility for your containerized applications. nosuid) does not mount accordingly. 4 days ago · The PV is still referencing its old PVC, in the claimRef, found under spec. If no SubPath is set and the NFS PV is set to the /nfs_sh Oct 2, 2025 · Every Kubernetes object also has a UID that is unique across your whole cluster. I've tried to search through the documentation to find a way to mount the volume with those permissions, however, I couldn't find any way to do it. cluster. A StorageClass provides a way for administrators to describe the classes of storage they offer. Aug 5, 2025 · Persistent Volumes This document describes persistent volumes in Kubernetes. Jul 18, 2024 · Kubernetes uses PersistentVolume (PV) and PersistentVolumeClaims (PVC) for such purposes. Jan 8, 2022 · Owners and Dependents In Kubernetes, some objects are owners of other objects. Nov 26, 2024 · This document describes the concept of a StorageClass in Kubernetes. There are different kinds of volume that you can use for different purposes, such as: populating a configuration file based on a ConfigMap or a Secret providing some temporary scratch space for a pod sharing a filesystem between two different containers in the same pod sharing a Jul 21, 2024 · Understanding Persistent Volumes (PVs) A PV in Kubernetes is a representation of a piece of storage that has been provisioned by an administrator or dynamically through storage plugins. Does anyone know whether you can specify in the configuration for either the PVC/PV or Deployment what UID to mount the volume with? If so, how? Jan 31, 2024 · Conclusion Properly managing user groups and file permissions in Kubernetes can significantly affect your application’s security and functionality. Scenario 3 - Multiple pods using a single PV as a shared volume. spec. The Service uses labels to allow the control I need to set uid and gid for proper permissions within a container and I can't seem to get the it working as expected. As a beginner it always bother me that if the pod life cycle comes to Dec 12, 2019 · Unfortunately we don't have this at the moment. This UID needs to be nullified to release the PV, allowing it to be adopted by a PVC with correct storageClass. Some volume types allow the Kubelet to change the ownership of that volume Sep 11, 2019 · Hi If I use pv/hostpath, then the owner of the following path /tmp/pv001 on the host will be used to mount the volume within the pod if we mount it using a PVC and define a pod/volume. Apr 5, 2018 · process, which runs as UID 200. uid. Nov 25, 2024 · In Kubernetes, a Persistent Volume Claim (PVC) is typically bound to a Persistent Volume (PV) using the storage class and the capacity requirements specified in the PVC. Or in the harder way, you can write an operator to watch a CRD which wraps the PVC and to display the usage of the PVC. May 3, 2018 · I have an application running over a POD in Kubernetes. Security context settings include, but are not limited to: Discretionary Access Control: Permission to access an object, like a file, is based on user ID (UID) and group ID (GID). Kubernetes has an additional layer of abstraction necessary for attaching a PV to a Pod: the PersistentVolumeClaim (PVC). #steps in Dockerfile #adding tomcat user and group and permission to /opt directory addgroup tomcat -g 1001 && \\ adduser Aug 5, 2025 · Persistent Volumes This document describes persistent volumes in Kubernetes. I have a startup script that creates a directory in /opt/var/logs (during container startup) and also starts tomcat service. For example, you can only have one Pod named myapp-1234 within the same namespace, but you can have one Pod and one Deployment that are each named myapp-1234. Mar 26, 2021 · In this scenario, each of the mounted volumes will have a different uid. g. Jul 17, 2025 · Volumes Kubernetes volumes provide a way for containers in a pod to access and share data via the filesystem. Introduction Managing storage is a distinct problem from managing compute instances. namespace!=default status. phase=Running Note:Field selectors By default, all the Pods (containers) cannot be run as root. Linux Automating theses changes is complicated due to: Kubernetes does not allow changes to most fields in an existing PersistentVolumeClaim Unless manually configured, the PVC is the only reference to dynamically provisioned PersistentVolumes Delete is the default reclaimPolicy for dynamically provisioned PersistentVolumes Set up a Samba Server on a Kubernetes cluster this example will create a new Samba Server (//smb-server. Here is my pv --- apiVersion: v1 kind: PersistentVolume metadata: annotations Oct 12, 2025 · A security context defines privilege and access control settings for a Pod or Container. Extra credit If you plan to have plenty of pods mounting storage from the same NFS server, you might want to consider building out a persistent volume first and then making claims from it. For example, a ReplicaSet is the owner of a set of Pods. For non-unique user-provided attributes, Kubernetes provides labels and annotations. The PersistentVolume subsystem provides an API for users and administrators that abstracts details of how storage is provided from how it is consumed Apr 8, 2022 · Perfect! Now files are owned by the correct UID and GID. In order to do that, I created a volume over the NFS and bound i Nov 20, 2023 · Using Azure File Share as Persistent Volumes with Kubernetes Kubernetes is like an ocean, the more you dig, the deeper it is. As the path has perhaps been defined as owned by root on the host, do you see a trick to change the ownership of such path /tmp/pv0xx to let the pod’s user which is maybe “1001” to access as RW such path May 14, 2024 · What happened? Setting the Volume subpath option at deployment with an NFS PV with a mount option (e. Kubernetes itself is Jul 28, 2020 · Using Pod specification attributes to force a prescribed UIDs, either to force the UID to one the application recognizes or to force the use of prescribed ports, is one of the Kubernetes constructs and attributes prone to be misunderstood, and used incorrectly by developers new to Kubernetes. 2. Different classes might map to quality-of-service levels, or to backup policies, or to arbitrary policies determined by the cluster administrators. Then you can tell Kubernetes to chown (sort of) the mount point of the volume for your pod by adding . Ownership is different from the labels and selectors mechanism that some resources also use. name=my-service metadata. phase=Pending This kubectl command selects all Pods for which the value of the status. Familiarity with volumes, StorageClasses and VolumeAttributesClasses is suggested. So my question is that a k8s way or Openshift way to define/change the uid and gid of the mounted volume. A PV represents the actual storage volume, and the PVC represents the request for storage that a Pod makes to get the actual storage. I have tried mountOptions which in talked about in Kubernetes Persistent Volume Claim mounted with wrong gid `mountOptions: #these options Oct 22, 2017 · First, find out the UID number your process is running as. phase field is Running: kubectl get pods --field-selector status. default. In this article, we’ll introduce PV and PVC fundamentals and elaborate on how to bind them correctly. Otherwise, the Pod is failed to create. This is because hostPath volumes directly mount directories from the host node's filesystem, and Kubernetes does not modify the file ownership or permissions of the host's file system when doing so. Oct 31, 2024 · Field selectors let you select Kubernetes objects based on the value of one or more resource fields. Here are some examples of field selector queries: metadata. securityContext. These owned objects are dependents of their owner. Jun 30, 2021 · I’m trying to run a tomcat container in K8S with a non-root user, to do so I set User ‘tomcat’ with the appropriate permission in Docker Image. . armstrong August 22, 2023, 2:07pm 1 Apr 21, 2017 · The Kubernetes securityContext, including fsGroup, does not change the ownership or permissions of files on hostPath volumes. Running as privileged or unprivileged. Jun 14, 2020 · Every time, the uid and gid of the volume mount into the Pod is always 'root root'. What our current solution is that we define an initContainer which run as root and use command 'chown [udi] [gid] [folder]' to change the ownership. I would like to store some output file logs on a persistent storage volume. But the process in the Pod is running as a non-root user, the process cannot read/write the mounted volume. local/share) with credential stored in secret smbcreds Use kubectl create secret to create smbcreds secret to store Samba Server username, password Nov 22, 2022 · Persistent volume claims A Persistent Volume (PV) represents an actual storage volume. fsGroup: spec: securityContext: fsGroup: 2000 fsGroup: integer: A special supplemental group that applies to all containers in a pod. The kubernetes examples repository has a good example of a persistent NFS volume and a persistent volume claim made from that volume. Production-Grade Container Scheduling and Management - kubernetes/kubernetes Aug 22, 2023 · How to ensure NFS PV is mounted with correct uid/gid permissions? General Discussions gunnar. The PersistentVolume subsystem provides an API for users and administrators that abstracts details of how storage is provided from how it is consumed Sep 6, 2019 · Hi If I use pv/hostpath, then the owner of the following path /tmp/pv001 on the host will be used to mount the volume within the pod if we mount it using a PVC and define a pod/volume. This blog attempt to describe the default behavior of Jan 31, 2025 · Learn how to configure VolumeMounts in Kubernetes to manage user group and file permissions for secure and reliable application deployments. What I often do is querying on Prometheus (because I have a Prom cluster there) for the metrics kubelet_volume_stats_used_bytes for the information. We run into the same problems here as we do in Scenario 1, except now you cannot even use the hack like running as a new user with the same uid as the PV. w1rusthwszm1n17nb6nvd9jbznxymtyxj7wyjypnolgnw3vyznp9