Do280 private warehouse persistent storage and chapter experiment

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Private warehouse persistent storage

Create a private warehouse persistent volume

OCP The internal warehouse is source-to-image(S2I) An important component of the process , This process is used to create pod.S2I The final output of the process is a container image, It was pushed to OCP Internal warehouse , It can then be used to deploy .

In the production environment , It is generally recommended to provide a persistent store for the internal Repository . otherwise , Re creating registry pod after ,S2I Created pod May not start . for example , stay master After the node restarts .

OpenShift The setup program configures and starts a default persistent Repository , The warehouse uses NFS share , from Inventory In the document openshift_hosted_registry_storage_* Variable definitions . In the production environment ,Red Hat It is recommended that persistent storage be provided by external dedicated storage , The server is configured for flexibility and high availability .

Advanced setup will NFS The server is configured to use external NFS Persistent storage on the server , stay [NFS] The one defined in the field NFS List of servers . The server and openshift_hosted_registry_storage* Variables are used together , To configure NFS The server .

Sample configuration ：

[OSEv3:vars]
openshift_hosted_registry_storage_kind=nfs		# Definition OCP Storage back end 
openshift_hosted_registry_storage_access_modes=['ReadWriteMany']	# Define access patterns , The default is ReadWriteMany, Indicates that multiple nodes are allowed to mount in read-write form 
openshift_hosted_registry_storage_nfs_directory=/exports		# Definition NFS On the server NFS Storage directory 
openshift_hosted_registry_storage_nfs_options='*(rw,root_squash)'	# Defines the storage volume NFS Options . These options are added to /etc/ exports.d/openshift-ansible.exports in .rw Options allow you to NFS Volume for read-write access ,root_squash Option prevents the root user of the remote connection from owning root Privilege , And for nfsnobody Assign users ID
openshift_hosted_registry_storage_volume_name=registry		# Define the... To be used for persistent repositories NFS The name of the catalog 
openshift_hosted_registry_storage_volume_size=40Gi			# Define persistent volume size 
... output omitted ...
[nfs]
services.lab.example.com

After installing and configuring the store for the persistent Repository ,OpenShift stay OpenShift Create a project named register-volume The persistent volume of . The capacity of the persistent volume is 40gb, And set up... According to the definition Retain Strategy . At the same time, the default project is pvc call pv.

[[email protected] ~]$ oc describe pv registry-volume
Name:            registry-volume	   # Define persistent volume name 
Labels:          <none>
Annotations:     pv.kubernetes.io/bound-by-controller=yes
StorageClass:
Status:          Bound
Claim:           default/registry-claim  # Define the statement to use persistent volumes 
Reclaim Policy:  Retain			       # Default persistent volume policy , have Retain Policy volumes are not erased after they are released from their claims 
Access Modes:    RWX			       # Define the access mode for persistent volumes , from Ansible inventory Of documents openshift_hosted_registry_storage_access_modes=['ReadWriteMany'] Variable definitions 
Capacity:        40Gi			       # Define the size of the persistent volume , from Ansible inventory Of documents openshift_hosted_registry_storage_volume_size Variable definitions 
Message:
Source:					            # Define the location of the storage back end and NFS share 
    Type:      NFS (an NFS mount that lasts the lifetime of a pod)
    Server:    services.lab.example.com
    Path:      /exports/registry
    ReadOnly:  false
Events:        <none>

Run the following command , confirm OpenShift The internal warehouse has been configured registry-volume By default PersistentVolumeClaim.

[[email protected] ~] oc describe dc/docker-registry | grep -A4 Volumes
  Volumes:
   registry-storage:
    Type:       PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
    ClaimName:  registry-claim
    ReadOnly:   false

OCP The internal warehouse will image and metadata Store as normal files and folders , This means that you can check PV Source storage , Check if the warehouse has written files to it .

In the production environment , This is through access to the outside NFS Server to complete . however , In this context ,NFS Sharing is in services Of VM The configuration of , therefore ssh to services see , For verification OCP Internal warehouse success will image Store in persistent storage .

Example ： A group called hello The application is in default Run... In namespace , The following command verifies that the image is stored in persistent storage .

[[email protected] ~] ssh [email protected] ls -l \
/var/export/registryvol/docker/registry/v2/repositories/default/

---

Chapter experiment

Environmental preparation

[[email protected] ~]$ lab install-prepare setup
[[email protected] ~]$ cd /home/student/do280-ansible
[[email protected] do280-ansible]$ ./install.sh

Tips ： If you already have a complete environment , Don't execute .

---

Prepare for this exercise

[[email protected] ~]$ lab storage-review setup

---

To configure NFS

This experiment does not explain in detail NFS Configuration and creation of , Use it directly /root/DO280/labs/deploy-volume/config-nfs.sh Script implementation , The specific script content can be viewed in the following ways .

meanwhile NFS from services Nodes provide .

[[email protected] ~]# less -FiX /root/DO280/labs/storage-review/config-review-nfs.sh
[[email protected] ~]# /root/DO280/labs/storage-review/config-review-nfs.sh # establish NFS
[[email protected] ~]# showmount -e # Validation verification 
Export list for services.lab.example.com:
/var/export/dbvol                *
/var/export/review-dbvol         *
/exports/prometheus-alertbuffer  *
/exports/prometheus-alertmanager *
/exports/prometheus              *
/exports/etcd-vol2               *
/exports/logging-es-ops          *
/exports/logging-es              *
/exports/metrics                 *
/exports/registry                *

---

Create persistent volume

[[email protected] ~]$ oc login -u admin -p redhat https://master.lab.example.com
[[email protected] ~]$ less -FiX /home/student/DO280/labs/storage-review/review-volume-pv.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  name: review-pv
spec:
  capacity:
    storage: 3Gi
  accessModes:
  - ReadWriteMany
  nfs:
    path: /var/export/review-dbvol
    server: services.lab.example.com
  persistentVolumeReclaimPolicy: Recycle
[[email protected] ~]$ oc create -f /home/student/DO280/labs/storage-review/review-volume-pv.yaml
[[email protected] ~]$ oc get pv		# see PV
NAME               CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM                                   STORAGECLASS   REASON    AGE
etcd-vol2-volume   1G         RWO            Retain           Bound       openshift-ansible-service-broker/etcd                            6d
registry-volume    40Gi       RWX            Retain           Bound       default/registry-claim                                           6d
review-pv          3Gi        RWX            Recycle          Available                                                                    5s

---

Deployment templates

[[email protected] ~]$ less -FiX /home/student/DO280/labs/storage-review/instructor-template.yaml
[[email protected] ~]$ oc create -n openshift -f /home/student/DO280/labs/storage-review/instructor-template.yaml
# Use templates to create applications to openshift namespace in 

---

Create project

[[email protected] ~]$ oc login -u developer -p redhat https://master.lab.example.com
[[email protected] ~]$ oc new-project instructor

---

web Deploy the application

Browser access ： https://master.lab.example.com

choice Catalog

choice PHP, And use instructor-template.

Set up Application Hostname, Then go straight to the next step , The template creates a database server .

single click Continue to project overview To monitor the build process of the application . From the framework of services provided , single click instructor. Click deploy configuration #1 The drop-down arrow next to the entry , Open the deployment panel . When the build is complete ,build Part of the Complete There should be a green check mark next to it .

---

Port forwarding

[[email protected] ~]$ oc login -u developer -p redhat https://master.lab.example.com
[[email protected] ~]$ oc get pod
NAME                 READY     STATUS      RESTARTS   AGE
instructor-1-build   0/1       Completed   0          15m
instructor-1-zqtwp   1/1       Running     0          14m
mysql-1-2k8kb        1/1       Running     0          15m 
[[email protected] ~]$ oc port-forward mysql-1-2k8kb 3306:3306

---

Fill the database

[[email protected] ~]$ mysql -h127.0.0.1 -u instructor -ppassword \
instructor < /home/student/DO280/labs/storage-review/instructor.sql
[[email protected] ~]$ mysql -h127.0.0.1 -u instructor -ppassword instructor -e "select * from instructors;"	
+------------------+-----------------+--------------------------------+----------------+-------+------------+---------------+
| instructorNumber | instructorName  | email                          | city           | state | postalCode | country       |
+------------------+-----------------+--------------------------------+----------------+-------+------------+---------------+
|              103 | DemoUser1       | [email protected] | Raleigh        | NC    | 27601      | United States |
|              112 | InstructorUser1 | [email protected] | Rio de Janeiro | RJ    | 22021-000  | Brasil        |
|              114 | InstructorUser2 | [email protected] | Raleigh        | NC    | 27605      | United States |
|              123 | InstructorUser3 | [email protected] | Sao Paulo      | SP    | 01310-000  | Brasil        |
+------------------+-----------------+--------------------------------+----------------+-------+------------+---------------+

---

Test access

workstations Browser access ：http://instructor.apps.lab.example.com

---

Test add data

---

Validation verification

[[email protected] ~]$ lab storage-review grade		# Environment script judgment experiment 

---

Clear the experiment

[[email protected] ~]$ oc login -uadmin -predhat
[[email protected] ~]$ oc delete project instructor
[[email protected] ~]$ oc delete pv review-pv
[[email protected] ~]$ ssh [email protected]
[[email protected] ~]# rm -rf /var/export/review-dbvol
[[email protected] ~]# rm -f /etc/exports.d/review-dbvol.exports

---

summary

• Red Hat OpenShift Container platform use PersistentVolumes (PVs) by pods Provide persistent storage .
• OpenShift Project use PersistentVolumeClaim (PVC) Resources to request that PV Assigned to project .
• OpenShift The installer configures and starts a default Repository , It is used from OpenShift Exported by the main program NFS share .
• A group of Ansible Variables are allowed to be OpenShift The default warehouse is configured with an external NFS Storage . This will create a persistent volume and a persistent volume declaration .

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That's all 【 Brother goldfish 】 Yes Chapter six DO280 Private warehouse persistent storage and chapter experiment Brief introduction and explanation of . I hope it can be helpful to the little friends who see this article .

Red hat Certification Column series ：
RHCSA special column ： entertain RHCSA authentication
RHCE special column ： entertain RHCE authentication
This article is included in RHCA special column ：RHCA memoir

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