I'm trying to mount a local directory to be used by a container in kubernetes, but getting this error:
$ kubectl logs mysql-pd
chown: changing ownership of '/var/lib/mysql/': Input/output error
minikube version: v0.33.1
docker for mac version: 2.0.0.2 (30215)
Engine: 18.09.1
Kubernetes: v1.10.11
I'm starting up minikube with mounted directory:
minikube start --mount-string /Users/foo/mysql_data:/mysql_data --mount
deployment.yml
apiVersion: v1
kind: Pod
metadata:
name: mysql-pd
spec:
containers:
- image: mysql:5.7
name: mysql-container
env:
- name: MYSQL_ROOT_PASSWORD
value: ""
- name: MYSQL_ALLOW_EMPTY_PASSWORD
value: "yes"
ports:
- containerPort: 3306
volumeMounts:
- mountPath: "/var/lib/mysql"
name: host-mount
volumes:
- name: host-mount
hostPath:
path: "/mysql_data"
As #Matthew L Daniel mentioned in the comments, the main purpose of using hostPath is to mount a local folder from your machine which is hosting minikube inside to the nested Pod, therefore it's not necessary to mount local directory inside to minikube. Also, take a look at this article which explains some restrictions about host folder mounting for the particular VM driver in minikube.
Related
I've figured out the syntax to mount a volume (Kubernetes YAML):
apiVersion: v1
kind: Pod
metadata:
...
spec:
containers:
- name: php
volumeMounts:
- mountPath: /app/db_backups
name: db-backups
readOnly: true
volumes:
- hostPath:
path: /mnt/c/Users/Mark/PhpstormProjects/proj/db_backups
type: DirectoryOrCreate
name: db-backups
And the volume does show when I drop into a shell:
kubectl --context docker-desktop exec --stdin --tty deploy/app-deployment-development -cphp -nmyns -- /bin/bash
But the db_backups directory is empty, so I guess the volume is backed by nothing -- it's not finding the volume on my Windows host machine.
I've tried setting the host path like C:\Users\Mark\PhpstormProjects\proj\db_backups but if I do that then my Deployment fails with a CreateContainerError:
Error: Error response from daemon: invalid volume specification: 'C:\Users\Mark\PhpstormProjects\proj\db_backups:/app/db_backups:ro'
So I guess it doesn't like the Windows-style filepath.
So what then? If neither style of path works, how do I get it to mount?
From here it is clear that, for WSL2 we need to mention the specific path before we are actually giving the path we desired in the host machine.
In your file you are giving like path: /mnt/c/Users/Mark/PhpstormProjects/proj/db_backups but you need to mention the path like this path: /run/desktop/mnt/host/path_of_directory_in_local_machine. The key is we need to mention /run/desktop/mnt/host/ before we are going to give the actual path to the directory.
You gave the type: DirectoryOrCreate in the above file, so that is creating an empty directory in the path you mentioned. Because it is not actually going to your desired path.
So try with this
apiVersion: v1
kind: Pod
metadata:
...
spec:
containers:
- name: php
volumeMounts:
- mountPath: /app/db_backups
name: db-backups
readOnly: true
volumes:
- hostPath:
path: /run/desktop/mnt/host/c/Users/Mark/PhpstormProjects/proj/db_backups
#In my case tested with path: /run/desktop/mnt/host/d/K8-files/voldir
type: DirectoryOrCreate
name: db-backups
It worked in our case, we created a directory in 'd' drive so we used this path: /run/desktop/mnt/host/d/K8-files/voldir. So try giving /run/desktop/mnt/host/ before the actual path.
For more information refer this Link
I have a local image that runs fine this way:
docker run -p 8080:8080 -v C:\Users\moritz\Downloads\1\imageService\examples1:/images -v C:\Users\moritz\entwicklung\projekte\imageCluster\logs:/logs imageservice
Now i want this to run as Kubernetes (using built in from Docker-for-Windows v1.19.7) deployment:
apiVersion: apps/v1
kind: Deployment
metadata:
name: image-service
spec:
selector:
matchLabels:
app: image-service
template:
metadata:
labels:
app: image-service
spec:
containers:
- name: image-service
image: "imageservice"
resources:
limits:
cpu: "0.9"
memory: "1Gi"
ports:
- name: http
containerPort: 8080
volumeMounts:
- mountPath: /images
name: image-volume
- mountPath: /logs
name: log-volume
volumes:
- name: image-volume
hostPath:
path: "c:\\Users\\moritz\\Downloads\\1\\imageService\\examples1"
type: Directory
- name: log-volume
hostPath:
path: /mnt/c/Users/moritz/entwicklung/projekte/imageCluster/logs
type: Directory
As you see i tried different ways to set up my host path on windows machine but i always get:
Warning FailedMount 0s (x4 over 4s) kubelet MountVolume.SetUp failed for volume "log-volume" : hostPath type check failed: /mnt/c/Users/moritz/entwicklung/projekte/imageCluster/logs is not a directory
Warning FailedMount 0s (x4 over 4s) kubelet MountVolume.SetUp failed for volume "image-volume" : hostPath type check failed: c:\Users\moritz\Downloads\1\imageService\examples1 is not a directory
I also tried other variants (for both):
C:\Users\moritz\entwicklung\projekte\imageCluster\logs
C:/Users/moritz/entwicklung/projekte/imageCluster/logs
So how to correctly setup these windows host path. (The next step would be to set them as environment variable.)
Little update:
removing type: Directory helps to get rid of the error and pod is starting but the mounts are not working. If i "look" into container in /images i don't see the images i have on my host and i don't see any logs in log mount while in container /logs contains the expected files.
in meantime i also tried (no avail)
/host_mnt/c/...
/C/Users/...
//C/Users/...
As mentioned here, you can use below hostPath to make it work on wsl2.
// C:\someDir\volumeDir
hostPath:
path: /run/desktop/mnt/host/c/someDir/volumeDir
type: DirectoryOrCreate
There is also an example you can use.
apiVersion: v1
kind: Pod
metadata:
name: test-localpc
spec:
containers:
- name: test-webserver
image: ubuntu:latest
command: ["/bin/sh"]
args: ["-c", "apt-get update && apt-get install curl -y && sleep 600"]
volumeMounts:
- mountPath: /run/desktop/mnt/host/c/aaa
name: mydir
- mountPath: /run/desktop/mnt/host/c/aaa/1.txt
name: myfile
volumes:
- name: mydir
hostPath:
# Ensure the file directory is created.
path: /run/desktop/mnt/host/c/aaa
type: DirectoryOrCreate
- name: myfile
hostPath:
path: /run/desktop/mnt/host/c/aaa/1.txt
type: FileOrCreate
I am trying to mount a volume within a Kubernetes pod (running linux) to a host folder on Windows 10. The pod starts up without issue, however, the data in the volumes aren't being reflected within the Pod and data set in the Pod isn't being reflected on the Windows host.
Here is my persistent volume:
kind: PersistentVolume
apiVersion: v1
metadata:
name: "elastic-search-persistence"
labels:
volume: persistence
spec:
storageClassName: hostpath
capacity:
storage: 5Gi
accessmodes:
- ReadWriteMany
hostPath:
path: /c/temp/es
Here is my persistent claim:
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: "elastic-search-persistence-claim"
spec:
storageClassName: hostpath
volumeName: "elastic-search-persistence"
accessModes:
- ReadWriteMany
resources:
requests:
storage: 5Gi
And here is my Pod using the above persistent volumes...
apiVersion: v1
kind: Pod
metadata:
name: windows-volume-demo
spec:
containers:
- name: windows-volume-demo
image: busybox
command: [ "sh", "-c", "sleep 1h" ]
volumeMounts:
- name: windows-volume-data-storage
mountPath: /data/demo
securityContext:
allowPrivilegeEscalation: true
volumes:
- name: windows-volume-data-storage
persistentVolumeClaim:
claimName: elastic-search-persistence-claim
I can start everything fine, however, when I create a file in my C:\temp\es folder on my Windows host, that file doesn't show inside the /data/demo folder in the Pod. And the reverse is also true. When I exec into the Pod and create a file in the /data/demo folder, it doesn't show in the C:\temp\es folder on the Windows host.
The folder/file privileges are wide open for the C:\temp folder and the C:\temp\es folder. I also tried exec-ing into the Pod and changing the write privs for the /data/demo folder to wide open -- all with no success.
This configuration works as expected on a Mac host (changing the volume paths for the host to a Mac folder). I suspect it is a privilege/permissions issue for Windows, but I am at a loss as to how to find/fix it.
Any help would be greatly appreciated.
I am trying to load my existing local elastic search indices into kubernetes (version - minikube v1.9.2) elastic search pod.
What I finally understood is I have to use mountpath and hostpath combination to do that. Additionlay if I want to provide a custom index file (not the default one), then I have to use a configMap to override path.data of config/elasticsearch.yml
I did those as below and it created a directory in mount path and update config/elasticsearch.yml file but a mount path directory does not contain the host path directory’s content.
I could not figure out the reason behind it. Could some one let me know what am I doing wrong here?
Then went I head and manually copied indexes from local host to kubernetes pod using
kubectl cp localelasticsearhindexdirectory podname:/data/elk/
But then I tried do a elastic search and it gives me a empty result ( even though index manually copied).
If I use the same index with a local elastic search ( not on kubernetes) then I can get the result.
Could someone please give some advice to diagnose following issues
Why mount path does not have the hostpjths content
How to debug / What steps should I follow understand why it’s not able to get the result with the elasticsearch on pod?
kind: Deployment
metadata:
name: elasticsearch
spec:
selector:
matchLabels:
run: elasticsearch
replicas: 1
template:
metadata:
labels:
run: elasticsearch
spec:
containers:
- image: docker.elastic.co/elasticsearch/elasticsearch:6.6.1
name: elasticsearch
imagePullPolicy: IfNotPresent
env:
- name: discovery.type
value: single-node
- name: cluster.name
value: elasticsearch
ports:
- containerPort: 9300
name: nodes
- containerPort: 9200
name: client
volumeMounts:
- name: storage
mountPath: /data/elk
- name: config-volume
mountPath: /usr/share/elasticsearch/config/elasticsearch.yml
subPath: elasticsearch.yml
volumes:
- name: config-volume
configMap:
name: elasticsearch-config
- name: storage
hostPath:
path: ~/elasticsearch-6.6.1/data
---
apiVersion: v1
kind: ConfigMap
metadata:
name: elasticsearch-config
data:
elasticsearch.yml: |
cluster:
name: ${CLUSTER_NAME:elasticsearch-default}
node:
master: ${NODE_MASTER:true}
data: ${NODE_DATA:true}
name: ${NODE_NAME:node-1}
ingest: ${NODE_INGEST:true}
max_local_storage_nodes: ${MAX_LOCAL_STORAGE_NODES:1}
processors: ${PROCESSORS:1}
network.host: ${NETWORK_HOST:_site_}
path:
data: ${DATA_PATH:"/data/elk"}
repo: ${REPO_LOCATIONS:[]}
bootstrap:
memory_lock: ${MEMORY_LOCK:false}
http:
enabled: ${HTTP_ENABLE:true}
compression: true
cors:
enabled: true
allow-origin: "*"
discovery:
zen:
ping.unicast.hosts: ${DISCOVERY_SERVICE:elasticsearch-discovery}
minimum_master_nodes: ${NUMBER_OF_MASTERS:1}
xpack:
license.self_generated.type: basic ```
**service.yaml**
```apiVersion: v1
kind: Service
metadata:
name: elasticsearch
labels:
service: elasticsearch
spec:
ports:
- name: client
port: 9200
protocol: TCP
targetPort: 9200
- name: nodes
port: 9300
protocol: TCP
targetPort: 9300
type: NodePort
selector:
run: elasticsearch```
Solution in HostPath with minikube - Kubernetes worked for me.
To mount a local directory into a pod in minikube (version - v1.9.2), you have to mount that local directory into minikube then use minikube mounted path in hostpath
(https://minikube.sigs.k8s.io/docs/handbook/mount/).
minikube mount ~/esData:/indexdata
📁 Mounting host path /esData into VM as /indexdata ...
▪ Mount type: <no value>
▪ User ID: docker
▪ Group ID: docker
▪ Version: 9p2000.L
▪ Message Size: 262144
▪ Permissions: 755 (-rwxr-xr-x)
▪ Options: map[]
▪ Bind Address: 192.168.5.6:55230
🚀 Userspace file server: ufs starting
✅ Successfully mounted ~/esData to /indexdata
📌 NOTE: This process must stay alive for the mount to be accessible ...
You have to run minikube mount in a separate terminal because it starts a process and stays there until you unmount.
Instead of doing it as Deployment as in the original question, now I am doing it as Statefulset but the same solution will work for Deployment also.
Another issue which I faced during mounting was elastic search server pod was throwing java.nio.file.AccessDeniedException: /usr/share/elasticsearch/data/nodes . Then I saw here that I have to use initContainers to set full permission in /usr/share/elasticsearch/data/nodes.
Please see my final yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: elasticsearch
spec:
serviceName: "elasticsearch"
replicas: 1
selector:
matchLabels:
app: elasticsearch
template:
metadata:
labels:
app: elasticsearch
spec:
initContainers:
- name: set-permissions
image: registry.hub.docker.com/library/busybox:latest
command: ['sh', '-c', 'mkdir -p /usr/share/elasticsearch/data && chown 1000:1000 /usr/share/elasticsearch/data' ]
volumeMounts:
- name: data
mountPath: /usr/share/elasticsearch/data
containers:
- name: elasticsearch
image: docker.elastic.co/elasticsearch/elasticsearch:6.6.1
env:
- name: discovery.type
value: single-node
ports:
- containerPort: 9200
name: client
- containerPort: 9300
name: nodes
volumeMounts:
- name: data
mountPath: /usr/share/elasticsearch/data
volumes:
- name: data
hostPath:
path: /indexdata
---
apiVersion: v1
kind: Service
metadata:
name: elasticsearch
labels:
service: elasticsearch
spec:
ports:
- port: 9200
name: client
- port: 9300
name: nodes
type: NodePort
selector:
app: elasticsearch
I'm building a micro service in Golang which is going to live in a Kubernetes cluster. I'm developing it and using Minikube to run a copy of the cluster locally.
The problem I ran into is that if I run my application inside of the container using go run main.go, I need to kill the pod for it to detect changes and update what is running.
I tried using a watcher for the binary so that the binary is updated on every save and a binary is running inside the pod, but even after compiling the new version, minikube is running the old one.
Any suggestion?
Here is my deployment file for running the MS locally:
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
labels:
name: pokedex
name: pokedex
spec:
template:
metadata:
labels:
name: pokedex
spec:
volumes:
- name: source
hostPath:
path: *folder where source resides*
containers:
- name: pokedex
image: golang:1.8.5-jessie
workingDir: *folder where source resides*
command: ["./pokedex"] # Here I tried both the binary and go run main.go
ports:
- containerPort: 8080
name: go-server
protocol: TCP
volumeMounts:
- name: source
mountPath: /source
env:
- name: GOPATH
value: /source