问题
I try, I try, but Rancher 2.1 fails to deploy the "mongo-replicaset" Catalog App, with Local Persistent Volumes configured.
How to correctly deploy a mongo-replicaset with Local Storage Volume? Any debugging techniques appreciated since I am new to rancher 2.
I follow the 4 ABCD steps bellow, but the first pod deployment never ends. What's wrong in it? Logs and result screens are at the end. Detailed configuration can be found here.
Note: Deployment without Local Persistent Volumes succeed.
Note: Deployment with Local Persistent Volume and with the "mongo" image succeed (without replicaset version).
Note: Deployment with both mongo-replicaset and with Local Persistent Volume fails.
Step A - Cluster
Create a rancher instance, and:
- Add three nodes: a worker, a worker etcd, a worker control plane
- Add a label on each node: name one, name two and name three for node Affinity
Step B - Storage class
Create a storage class with these parameters:
- volumeBindingMode : WaitForFirstConsumer saw here
- name : local-storage
Step C - Persistent Volumes
Add 3 persistent volumes like this:
- type : local node path
- Access Mode: Single Node RW, 12Gi
- storage class: local-storage
- Node Affinity: name one (two for second volume, three for third volume)
Step D - Mongo-replicaset Deployment
From catalog, select Mongo-replicaset and configure it like that:
- replicaSetName: rs0
- persistentVolume.enabled: true
- persistentVolume.size: 12Gi
- persistentVolume.storageClass: local-storage
Result
After doing ABCD steps, the newly created mongo-replicaset app stay infinitely in "Initializing" state.
The associated mongo workload contain only one pod, instead of three. And this pod has two 'crashed' containers, bootstrap and mongo-replicaset.
Logs
This is the output from the 4 containers of the only running pod. There is no error, no problem.
I can't figure out what's wrong with this configuration, and I don't have any tools or techniques to analyze the problem. Detailed configuration can be found here. Please ask me for more commands results.
Thanks you
回答1:
All this configuration is correct.
It's missing a detail since Rancher is a containerized deployment of kubernetes. Kubelets are deployed on each node in docker containers. They don't access to OS local folders.
It's needed to add a volume binding for the kubelets, like that K8s will be able to create the mongo pod with this same binding.
In rancher: Edit the cluster yaml (Cluster > Edit > Edit as Yaml)
Add the following entry under "services" node:
kubelet:
extra_binds:
- "/mongo:/mongo:rshared"
来源：https://stackoverflow.com/questions/53008824/kubernetes-rancher-2-mongo-replicaset-with-local-storage-volume-deployment