I have done bitnami redis-cluster deployment using helm chart. I have followed below link for redis-cluster deployment-
https://github.com/bitnami/charts/tree/master/bitnami/redis-cluster
I wanted to enable redis logs, but not sure how to do it, as in the current bitnami redis image configuration file located at /opt/bitnami/redis/etc/redis.conf having parameter value logfile:"" as empty strings.
Please let me is there any ways to enable a redis server logs on each pod??
You can use helm --set flag to overwrite the default values in the redis.conf file.
// Add your custom configurations
$ export CUSTOM_CONFIG="logfile /data/logs/file.log"
// Apply those while installing
$ helm install redis bitnami/redis-cluster --set redis.configmap=$CUSTOM_CONFIG
You can check it from inside the pod:
$ kubectl exec -it redis-redis-cluster-0 -- cat /opt/bitnami/redis/etc/redis.conf
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logfile /data/logs/file.log
Related
I wanted to share a solution I did with kubernetes and have your opinion on best practice to do in such case. I'm still new to kubernetes.
I had a problem I wanted to be able to update my application by restarting my deployment pod that execute all the necessary action to do that already in command start.
I'm using microk8s and I wanted to just go to the good folder and execute microk8s kubectl apply -f myfilename and let kubernetes handle the rest with rolling update.
My issue was how to set dynamic value inside my .yaml file so the command would detect the change and start the process.
I've planned to do a bash script that do the job like the following:
file="my-file-deployment.yaml"
oldstr=`grep 'my' $file | xargs`
timestamp="$(date +"%Y-%m-%d-%H:%M:%S")"
newstr="value: my-version-$timestamp"
sed -i "s/$oldstr/$newstr/g" $file
echo "old version : $oldstr"
echo "Replaced String : $newstr"
sudo microk8s kubectl apply -f $file
on my deployment.yaml file I'm giving the following env:
env:
- name: version
value: my-version-2022-09-27-00:57:15
I'm switching with timestamp to a new value then I launch the command:
microk8s kubectl apply -f myfilename
it is working great for the moment. I still have to configure startupProbe to have a better rolling update execution because I'm having few second downtime which isn't cool.
Is there a better solution to work with rolling update using microk8s?
If you are trying to trigger a rolling update on your deployment (assuming it is a deployment), you can patch the deployment and let the cluster handle the rollout. Here's a trick I use and it's literally a one-liner:
kubectl -n {namespace} patch deployment {name-of-your-deployment} \
-p "{\"spec\":{\"template\":{\"metadata\":{\"annotations\":{\"date\":\"`date +'%s'`\"}}}}}"
This will patch your deployment, adding an annotation to the template block. In this way, the cluster thinks there is a change requiring an update to the deployment's pods, and will cycle them while following the rollingUpdate clause.
The date +'%s' will resolve to a different number each time so every time you run this, it will cause the cluster to cycle the deployment's pods.
We use this trick to force a rolling update when we have done an update that requires our pods to be restarted.
You can accompany this with the rollout status command to wait for the update to complete:
kubectl rollout status deployment/{name-of-your-deployment} -n {namespace}
So a complete line would be something like this if I wanted to rolling update my nginx deployment and wait for it to complete:
kubectl -n nginx patch deployment nginx \
-p "{\"spec\":{\"template\":{\"metadata\":{\"annotations\":{\"date\":\"`date +'%s'`\"}}}}}" \
&& kubectl rollout status deployment/nginx -n nginx
One caveat, though. Using kubectl patch does not make changes to the yamls on disk, so if you wanted a copy of the change recorded locally, such as for auditing purposes, similar to what you are doing at the moment, then you could adapt this to do it as a dry-run and redirect output to file:
kubectl -n nginx patch deployment nginx \
-p "{\"spec\":{\"template\":{\"metadata\":{\"annotations\":{\"date\":\"`date +'%s'`\"}}}}}" \
--dry-run=client \
-o yaml >patched-nginx.yaml
I have this bash script:
#!/bin/bash
USERNAME=$1
WORKDIR='dir_'$USERNAME
mkdir deployment/$WORKDIR
cat deployment/deploy.yml > deployment/$WORKDIR/deploy.yml
sed -i 's/alopezfu/'$USERNAME'/g' deployment/$WORKDIR/deploy.yml
kubectl apply -f deployment/$WORKDIR/deploy.yml
rm -rf deployment/$WORKDIR/
And i use exec funcition in PHP for run.
And i get this messege in /var/log/apache/error.log
To view or setup config directly use the 'config' command.
error: no configuration has been provided, try setting KUBERNETES_MASTER environment variable
error: Missing or incomplete configuration info. Please point to an existing, complete config file:
Via the command-line flag --kubeconfig
Via the KUBECONFIG environment variable
In your home directory as ~/.kube/config
I need help 🙏
Since you are running the script as a diferent user, you need to "tell" to kubectl where is the configuration file.
This can be done setting the variable KUBECONFIG in your environment.
Supposing the kubernetes config file is in the dir /var/www/ with the correct permission to be readable, you can configure your php script like this:
<?php
$kubeconfig = "/var/www/config"; // The config file
putenv("KUBECONFIG=$kubeconfig"); // set the environment variable KUBECONFIG
$output = shell_exec("KUBECONFIG=$kubeconfig ; kubectl get pods -A"); // Runs the command
echo "<pre>$output</pre>"; // and return the expected output.
?>
Please be aware that:
Setting certain environment variables may be a potential security breach.
Some actions that should mitigate the impacts:
Make sure your config file is safe and not reachable from the browser;
Consider to create a serviceAccount with limited permissions;
Here you can find some useful commands and kubectl tips.
How to create a service account for kubectl
I am looking options to install confluent schema registry, is it possible to download and install registry alone and make it work with existing kafka setup ?
Thanks
Assuming you have Zookeeper/Kafka running already, you can easily run Confulent Schema Registry using Docker with running the following command:
docker run -p 8081:8081 -e \
SCHEMA_REGISTRY_KAFKASTORE_CONNECTION_URL=host.docker.internal:2181 \
-e SCHEMA_REGISTRY_HOST_NAME=localhost \
-e SCHEMA_REGISTRY_LISTENERS=http://0.0.0.0:8081 \
-e SCHEMA_REGISTRY_DEBUG=true confluentinc/cp-schema-registry:5.3.2
parameters:
-p 8081:8081 - will open the port 8081 between the container to your machine
SCHEMA_REGISTRY_KAFKASTORE_CONNECTION_URL - is your Zookeeper host and port, I'm using host.docker.internal to resolve local machine that is hosting Zookeeper (outside of the container)
SCHEMA_REGISTRY_HOST_NAME - The hostname advertised in Zookeeper. This is required if if you are running Schema Registry with multiple nodes. Hostname is required because it defaults to the Java canonical hostname for the container, which may not always be resolvable in a Docker environment.
SCHEMA_REGISTRY_LISTENERS - the Schema Registry host and port number to open
SCHEMA_REGISTRY_DEBUG Run in debug mode
note: the script was using the version 5.3.2, make sure this version is aligned with your Kafka version.
Yes you can use your existing Kafka setup, just match to the compatible version of Confluent Platform. Here are the docs on getting started
https://docs.confluent.io/current/schema-registry/docs/intro.html#installation
tl;dr download the platform to pull out the pieces you need or get the docker image and point it at your Kafka cluster.
I am getting Exception ( Determine Target Server Group )
Path parameter "app" value must not be null. when enabling server group. Can anyone tell me what I could be doing wrong? I can enable the server manually but when I put it in a stage it fails with the error.
Please upgrade to spinnaker version 1.17 That version solves issues with the enable server group stage.
To Upgrade Spinnaker:
Access halyard pod
get pods name
export HALYARD=$(kubectl -n spinnaker get pod -l app=halyard -oname | cut -d'/' -f 2)
Access Halyard pod with bash
kubectl -n spinnaker exec -it ${HALYARD} /bin/bash
Obtain the version by running Halyard Command
hal version bom
Set the version you want to use. Refer to the releases page Versions1
export UPGRADE_VERSION=1.17.6
hal config version edit --version $UPGRADE_VERSION
Deploy and apply the new version with hal
hal deploy apply
I have installed redis cluster 3.0.0. But Want to upgrade it to 3.0.7. Can somebody tell me the steps to do it?
I don't want to loose any data. And don't want any downtime either.
Steps I did when upgrading from 2.9.101 to 3.0 release. I hope it will do for upgrading to 3.0.7 too.
Compile 3.0.7 from the source and start several instances with cluster enabled.
Let the 3.0.7 instances replicate the 3.0.0 instances as slave
Connect to each 3.0.7 instance and do a manual failover, then the 3.0.0 masters would become slaves after several seconds.
Wait for your application to connect to the new masters; also check the configuration files, and modify the entries to the new masters on your need
Remove those slaves
UPDATE : Docker approach
As it's probably unable to replacing the binary executable while the process is still alive, you could do it by run some Redis in docker.
First you should install docker on your machine and pull the Redis image, or pull a basic OS image and manually build Redis in it, whatever
Based on this image, you are supposed to
copy your current redis.conf into it
make sure the dir exists in the image (cluster-config-file could be the same for all the containers as they are saved individually in their own fs)
make sure the directory for logfile exists and is not the same as dir (we will later map this directory to the host)
leave port logfile anything you like, as they are specified when a container is started
commit the image as redis-3.0.7
Now launch a containerized Redis. I suppose your logfile is located in /var/log/redis/, this Redis binds :8000, and your config file in the image is /etc/redis/redis.conf
docker run -d --net=host -v /var/log/redis:/var/log/redis \
-p 8000:8000 -t redis-3.0.7 \
/usr/bin/redis-server /etc/redis/redis.conf \
--port 8000 \
--logfile /var/log/redis/redis_8000.log
Now you have a Redis 3.0.7 instance, and are ready to finish the rest steps in the previous part.