问题
I am converting a docker-compose file to kubernetes using kompose running the follwing command:
$kompose convert -f docker-compose.yml -o kubernetes_image.yaml
After the command finish the ouput is the following.
WARN Volume mount on the host "/usr/docker/adpater/dbdata" isn't supported - ignoring path on the host
INFO Network integration is detected at Source, shall be converted to equivalent NetworkPolicy at Destination
WARN Volume mount on the host "/usr/docker/adpater/license.json" isn't supported - ignoring path on the host
WARN Volume mount on the host "/usr/docker/adpater/certificates/ssl.crt" isn't supported - ignoring path on the host
WARN Volume mount on the host "/usr/docker/adpater/certificates/ssl.key" isn't supported - ignoring path on the host
WARN Volume mount on the host "/usr/docker/adpater/server.xml" isn't supported - ignoring path on the host
INFO Network integration is detected at Source, shall be converted to equivalent NetworkPolicy at Destination
To push the converted file to kubernetes I run the follwoing command:
$kubectl apply -f kubernetes_image.yaml
NAME READY STATUS RESTARTS AGE
mysql-557dd849c8-bsdq7 1/1 Running 1 17h
tomcat-7cd65d4556-spjbl 0/1 CrashLoopBackOff 76 18h
if I run: $ kubectl describe pod tomcat-7cd65d4556-spjbl I get the following message:
Last State: Terminated
Reason: ContainerCannotRun
Message: OCI runtime create failed: container_linux.go:349: starting container process caused "process_linux.go:449: container init caused \"rootfs_linux.go:58: mounting \\\"/usr/docker/adapter/server.xml\\\" to rootfs \\\"/var/lib/docker/overlay2/a6df90a0ef4cbe8b2a3fa5352be5f304cd7b648fb1381492308f0a7fceb931cc/merged\\\" at \\\"/var/lib/docker/overlay2/a6df90a0ef4cbe8b2a3fa5352be5f304cd7b648fb1381492308f0a7fceb931cc/merged/usr/local/tomcat/conf/server.xml\\\" caused \\\"not a directory\\\"\"": unknown: Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type
Exit Code: 127
Started: Sun, 31 May 2020 13:35:00 +0100
Finished: Sun, 31 May 2020 13:35:00 +0100
Ready: False
Restart Count: 75
Environment: <none>
Mounts:
/run/secrets/rji_license.json from tomcat-hostpath0 (rw)
/usr/local/tomcat/conf/server.xml from tomcat-hostpath3 (rw)
/usr/local/tomcat/conf/ssl.crt from tomcat-hostpath1 (rw)
/usr/local/tomcat/conf/ssl.key from tomcat-hostpath2 (rw)
/var/run/secrets/kubernetes.io/serviceaccount from default-token-8dhnk (ro)
This is my docker-compose.yml file:
version: '3.6'
networks:
integration:
services:
mysql:
environment:
MYSQL_USER: 'integrationdb'
MYSQL_PASSWORD: 'password'
MYSQL_ROOT_PASSWORD: 'password'
image: db:poc
networks:
- integration
ports:
- '3306:3306'
restart: always
volumes:
- ./dbdata:/var/lib/mysql
tomcat:
image: adapter:poc
networks:
- integration
ports:
- '8080:8080'
- '8443:8443'
restart: always
volumes:
- ./license.json:/run/secrets/rji_license.json
- ./certificates/ssl.crt:/usr/local/tomcat/conf/ssl.crt
- ./certificates/ssl.key:/usr/local/tomcat/conf/ssl.key
- ./server.xml:/usr/local/tomcat/conf/server.xml
Versions of the tools:
kompose: 1.21.0 (992df58d8)
docker: 19.03.9
kubectl:Major:"1", Minor:"18"
I think my challange here is whithin this type of volumes or files, I dont know how can I migrate or convert them to kubernetes and put the tomcat pod running fine. Could someone give me a hand?
volumes:
- ./license.json:/run/secrets/rji_license.json
- ./certificates/ssl.crt:/usr/local/tomcat/conf/ssl.crt
- ./certificates/ssl.key:/usr/local/tomcat/conf/ssl.key
- ./server.xml:/usr/local/tomcat/conf/server.xml
thanks in advance.
回答1:
When Kompose warns you:
WARN Volume mount on the host "/usr/docker/adpater/license.json" isn't supported - ignoring path on the host
It means that it can't translate this fragment of the docker-compose.yml file into Kubernetes syntax:
volumes:
- ./license.json:/run/secrets/rji_license.json
In native Kubernetes, you'd need to provide this content in ConfigMap or Secret objects, and then mount the file into the pod. You can't directly access content on the system from which you're launching the containers.
You can't really get around directly working with the Kubernetes YAML files here. You could run kompose convert to generate the skeleton files, but then you'll need to edit those to add the ConfigMaps, PersistentVolumeClaims (for the database storage), and relevant volume and mount declarations, and then run kubectl apply -f to actually run them. I'd check the Kubernetes YAML files into source control, and maintain them in parallel with your Docker Compose setup.
回答2:
Move2Kube (which does support docker-compose translation), can handle this case and tries to convert the volumes by interacting with you.
? 6. [] What type of container registry login do you want to use?
Hints:
[Docker login from config mode, will use the default config from your local machine.]
No authentication
? 7. Do you want to create PVC for host path [/Users/ashok/wksps/hc/temp/test2/src/dbdata]?:
Hints:
[Use PVC for persistent storage wherever applicable]
Yes
? 8. Do you want to create PVC for host path [/Users/ashok/wksps/hc/temp/test2/src/license.json]?:
Hints:
[Use PVC for persistent storage wherever applicable]
No
? 9. Do you want to create PVC for host path [/Users/ashok/wksps/hc/temp/test2/src/certificates/ssl.crt]?:
Hints:
[Use PVC for persistent storage wherever applicable]
No
? 10. Do you want to create PVC for host path [/Users/ashok/wksps/hc/temp/test2/src/certificates/ssl.key]?:
Hints:
[Use PVC for persistent storage wherever applicable]
No
? 11. Do you want to create PVC for host path [/Users/ashok/wksps/hc/temp/test2/src/server.xml]?:
Hints:
[Use PVC for persistent storage wherever applicable]
No
? 12. Which storage class to use for persistent volume claim [vol17655897939759777588] used by [mysql]
Hints:
[If you have a custom cluster, you can use collect to get storage classes from it.]
default
? 13. Provide the ingress host domain
Hints:
[Ingress host domain is part of service URL]
myproject.com
? 14. Provide the TLS secret for ingress
Hints:
[Enter TLS secret name]
If the above choices were made Move2Kube creates the following artifacts:
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
move2kube.konveyor.io/service.expose: "true"
creationTimestamp: null
labels:
move2kube.konveyor.io/network/integration: "true"
move2kube.konveyor.io/service: tomcat
name: tomcat
spec:
replicas: 2
selector:
matchLabels:
move2kube.konveyor.io/service: tomcat
strategy: {}
template:
metadata:
annotations:
move2kube.konveyor.io/service.expose: "true"
creationTimestamp: null
labels:
move2kube.konveyor.io/network/integration: "true"
move2kube.konveyor.io/service: tomcat
name: tomcat
spec:
containers:
- image: adapter:poc
imagePullPolicy: Always
name: tomcat
ports:
- containerPort: 8080
protocol: TCP
- containerPort: 8443
protocol: TCP
resources: {}
volumeMounts:
- mountPath: /run/secrets/rji_license.json
name: vol16871681589659214643
- mountPath: /usr/local/tomcat/conf/ssl.crt
name: vol12635587774184387470
- mountPath: /usr/local/tomcat/conf/ssl.key
name: vol7446232639477381794
- mountPath: /usr/local/tomcat/conf/server.xml
name: vol4920239289720818926
restartPolicy: Always
volumes:
- hostPath:
path: /Users/ashok/wksps/hc/temp/test2/src/license.json
name: vol16871681589659214643
- hostPath:
path: /Users/ashok/wksps/hc/temp/test2/src/certificates/ssl.crt
name: vol12635587774184387470
- hostPath:
path: /Users/ashok/wksps/hc/temp/test2/src/certificates/ssl.key
name: vol7446232639477381794
- hostPath:
path: /Users/ashok/wksps/hc/temp/test2/src/server.xml
name: vol4920239289720818926
status: {}
and
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
move2kube.konveyor.io/service.expose: "true"
creationTimestamp: null
labels:
move2kube.konveyor.io/network/integration: "true"
move2kube.konveyor.io/service: mysql
name: mysql
spec:
replicas: 2
selector:
matchLabels:
move2kube.konveyor.io/service: mysql
strategy: {}
template:
metadata:
annotations:
move2kube.konveyor.io/service.expose: "true"
creationTimestamp: null
labels:
move2kube.konveyor.io/network/integration: "true"
move2kube.konveyor.io/service: mysql
name: mysql
spec:
containers:
- env:
- name: MYSQL_USER
value: integrationdb
- name: MYSQL_PASSWORD
value: password
- name: MYSQL_ROOT_PASSWORD
value: password
image: db:poc
imagePullPolicy: Always
name: mysql
ports:
- containerPort: 3306
protocol: TCP
resources: {}
volumeMounts:
- mountPath: /var/lib/mysql
name: vol17655897939759777588
restartPolicy: Always
volumes:
- name: vol17655897939759777588
persistentVolumeClaim:
claimName: vol17655897939759777588
status: {}
and
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
creationTimestamp: null
name: vol17655897939759777588
spec:
resources:
requests:
storage: 100Mi
storageClassName: default
volumeName: vol17655897939759777588
status: {}
Essentially depending on your choice Move2Kube will create the appropriate artifacts for you.
You can check out how it works in https://konveyor.github.io/move2kube/tutorials/docker-compose/.
来源：https://stackoverflow.com/questions/62115772/convert-docker-compose-yml-file-to-kubernetes