Redis Master Slave

This is an experimental master slave set up on kubetnets

Steps .

1. Create a linux virtiual machine (if you are running a non-linux machine)

1. Install vagrant & virtual box
2. Run the script in terminal

   	vagrant up
   	vagrant ssh
   	cd /vagrant
   	

2. Build the redis image

Prereq: install docker if you are skipping step 1

1. Run the script in terminal

   	docker build -t myredis3.2   .
   

2. see whether the image is build as below .

   	docker  images
   

   You should see below out put

   	
   	[vagrant@redisimagebuilderv1 vagrant]$ docker  images
   	REPOSITORY          TAG                 IMAGE ID            CREATED              SIZE
   	myredis3            latest              9c58c6fe09bc        About a minute ago   9.399 MB
   	alpine              3.5                 88e169ea8f46        2 weeks ago          3.98 MB
   

3. Test the redis image

1. Run the script in terminal

   	docker run -e MASTER=true  myredis3
   

   You should see below out put

   	
   				    _.-``    `.  `_.  ''-._           Redis 3.2.5 (c72176ef/0) 64 bit
   		  .-`` .-```.  ```\/    _.,_ ''-._                                   
   		 (    '      ,       .-`  | `,    )     Running in standalone mode
   		 |`-._`-...-` __...-.``-._|'` _.-'|     Port: 6379
   		 |    `-._   `._    /     _.-'    |     PID: 6
   		  `-._    `-._  `-./  _.-'    _.-'                                   
   		 |`-._`-._    `-.__.-'    _.-'_.-'|                                  
   		 |    `-._`-._        _.-'_.-'    |           http://redis.io        
   		  `-._    `-._`-.__.-'_.-'    _.-'                                                        
   
   

4. Push the image to a docker repository .  

1. Run the script in terminal

   	# tag the image .  
   		docker tag myredis3 jojiisacth/redis . 
   	# push the image  
   		docker push   jojiisacth/redis
   	

5. Running the redis in kubernets cluster .

Prereq: 1. You should have a running kubernets cluster and acces to it . 2. kubectl installed

1. Open a terminal in the K8 folder where we have YAML files are ressent . 2 Run the script in terminal

     kubectl create  -f masterRs.yaml 
     kubectl create  -f masterSrv.yaml 
     kubectl create  -f slaveRs.yaml 
   

6. Testing the deployment.

1 Run the script in terminal kubectl get pods You should see out put as below

	NAME                READY     STATUS    RESTARTS   AGE
	redismaster-yrq92   1/1       Running   0          33s
	redisslave-a01ko    1/1       Running   0          14s
	redisslave-gwm1n    1/1       Running   0          14s

7. Testing the redis master slave .

 1. Bash into master

	kubectl exec -it redismaster-yrq92 bash

 2. Open redis command line utility and add some data to redis

	bash-4.3# 
	redis-cli
	127.0.0.1:6379> set mykey  myvalue
	OK
	127.0.0.1:6379> get mykey
	"myvalue"

 3. Bash into slave

	kubectl exec -it redismaster-yrq92 bash

 4. Open redis command line utility view the date saved into master. Also note that when you try to save data it will not be allowed

	kubectl exec -it redisslave-a01ko  bash
	bash-4.3#                                                                                                                                                                                               
	bash-4.3# redis-cli  
	127.0.0.1:6379> get mykey
	"myvalue"
	
	127.0.0.1:6379> set my key  chnaged
	(error) READONLY You can't write against a read only slave.
	127.0.0.1:6379> 

This complete this experiment :)