Hi I 'm new to prometheus I have a task to make prometheus show systemd services metrics (I use grafana for visualization) I' m using stefanprodan/dockprom example as my starting point however I couldn't find how to enable systemd collector for node exporter in the node exporter section of the docker-compose.yml and also leave all the enabled by default collectors. Also I need help with getting that info to be sent into grafana. I would appreciate the code in the example or a place where I could find an adequate explanation how to do it like for dummies because I'm not experienced. Thanks in advance.
In order to enable the systemd collector in node_exporter, the command line flag --collector.systemd needs to be passed to the exporter (reference). The default collectors will remain enabled, so you don't need to worry about that.
In order to pass that flag to the application, you need to add that flag to the command portion of the nodeexporter section of the Docker Compose file (here)
In regards to sending the data to Grafana, as long as you have your Prometheus data source configured in Grafana, those metrics will show up automatically -- you don't need to update your Prometheus->Grafana when or removing metrics (or really ever, after initial setup).
Related
I am trying to get into the way of things with the Kubernetes but I'm facing a problem with hot reload.
In the development mode when I am just working on the code and I need the code be synchronized with the pods directly like in Docker when I use volumes to keep the state.
Is there any chance to make it work with the Kubernetes?
I would be thankful for any help with Kubernetes...
From the view of Cloud native(or kubernetes), the infrastructure is immutable and the Pods are the smallest deployable units. So you should replace the pod rather than change it(your code is part of the pod/image). so the correct process is: change code -> build image -> recreate pod in your env But actually, your process still could work just not follow the best practice of cloud native... –
vincent pli
Also, you can try Ksync, that allows you to synchronize application code between your local and Kubernetes cluster. Kindly ask you to refer to official documentation to read more about.
We just migrated to a kubernetes cluster, I was wondering if it is possible to send a kafka event when a container/pod finishes automatically with the stdout as message. Right now we are using fluentd with elastic search but the output of a pod is used as input for the next one, we need to poll constantly elastic search for when the output is ready and that causes performance issues on overall execution
I'm not sure of your current setup but my first thought would jump to:
Use something such as fluentd or Logstash on it's own pod per node
Configure volume access to Kubernetes log folder /var/log/containers/*
Use the Kafka output for either fluentd or Logstash with file input (tail) on the logging folder
This approach would require the configuration above on each node however but requires minimal configuration of logging locations etc..
It's not something I've personally configured but have considered it for the future.
More info here
I've got the EFK stack installed on kubernetes following this addon: https://github.com/kubernetes/kubernetes/tree/master/cluster/addons/fluentd-elasticsearch
What I want to achieve is having all the logs of the same pod together, and even maybe some other filters. But I don't want to configure the filter in kibana with the GUI, I'd like to have them preconfigured in the way that some of my known containers (the containers that I want to monitorize) are configured previously and installed when kibana rather than using an additional step to import/export them. I'd like to have the predefined filters in a way that, immediately after the installation, I can go to "discover", select the pod name that I want to see and then I see all the logs in the format:
In my understanding, that being the first time that I use this tech is near to zero, the in the fluentd-configmap.yml with the correct parameters should do the trick, but none of my tries has altered what I see in kibana.
Am I looking in the correct place for doing this or this filter is not for this use and I'm completely wasting my time? How could I do this filter in any case?
Any help, even if is only a hint, would be appreciated.
Our setup:
We are using kubernetes in GCP.
We have pods that write logs to a shared volume, with a sidecar container that sucks up our logs for our logging system.
We cannot just use stdout instead for this process.
Some of these pods are long lived and are filling up disk space because of no log rotation.
Question:
What is the easiest way to prevent the disk space from filling up here (without scheduling pod restarts)?
I have been attempting to install logrotate using: RUN apt-get install -y logrotate in our Dockerfile and placing a logrotate config file in /etc/logrotate.d/dynamicproxy but it doesnt seem to get run. /var/lib/logrotate/status never gets generated.
I feel like I am barking up the wrong tree or missing something integral to getting this working. Any help would be appreciated.
We ended up writing our own daemonset to properly collect the logs from the nodes instead of the container level. We then stopped writing to shared volumes from the containers and logged to stdout only.
We used fluentd to the logs around.
https://github.com/splunk/splunk-connect-for-kubernetes/tree/master/helm-chart/splunk-kubernetes-logging
In general, you should write logs to stdout and configure log collection tool like ELK stack. This is the best practice.
However, if you want to run logrotate as a separate process in your container - you may use Supervisor, which serves as a very simple init system and allows you to run as many parallel process in container as you want.
Simple example for using Supervisor for rotating Nginx logs can be found here: https://github.com/misho-kr/docker-appliances/tree/master/nginx-nodejs
If you write to the filesystem the application creating the logs should be responsible for rotation. If you are running a java application with logback or log4j it is simple configuration change. For other languages/frameworks it is usually similar.
If that is not an option you could use a specialized tool to handle the rotation and piping the output to it. One example would be http://cr.yp.to/daemontools/multilog.html
As method of last resort you could investigate to log into a named pipe (FIFO) instead of a real file and have some other process handling the retrieval and writing of the data - including the rotation.
Is there any documentation out there on sending logs from containers in K8s to an external ELK cluster running on EC2 instances?
We're in the process of trying to Kubernetes set up and I'm trying to figure out how to get the logging to work correctly. We already have an ELK stack setup on EC2 for current versions of the application but most of the documentation out there seems to be referring to ELK as it's deployed to the K8s cluster.
I am also working on the same cause.
First you should know what driver is being used by your docker containers to manage the logs (json driver/ journald etc - read here).
After that you should use some log collector in your architecture to send the logs to the Logstash endpoint. You can use filebeat/fluent bit. They are light weight alternatives to logstash/fluentd respectively. You must use one of them and not directly send your logs to logstash via syslog since these log shippers have a special functionality of enriching your logs with kubernetes metadata of the respective containers.
There might be lot of challenges after that. Parsing log data (multiline logs for example) etc. For an efficient pipeline, it’s better to do most of the work (i.e. extracting the date object from the logs etc) at the log sender side, than using the common logstash for this purpose that might be a bottle-neck.
Note that in case the container logs are not sent to stdout/stderr but written else-where, you might need to run filebeat/fluent-bit as side-car with your containers.
As for the links for documentation are concerned, I myself didn’t find anything documented in a single place on this, but the keywords that I mentioned over, reading about them I got to know many things.
Hope this helps.