We’re preparing to migrate our Backend API database from DynamoDB to AWS RDS with PostgreSQL, and finally decided to try out AWS RDS IAM database authentication, which appeared in 2021. IAM database authentication, as the name implies, allows us to authenticate to RDS using AWS IAM instead of the login-password from the database server itself.… Read More »
Let’s continue our series on cost optimization in AWS. Previous posts: AWS: cost optimization – purchasing RDS Reserved Instances AWS: Cost Explorer – costs checking on the CloudWatch Logs example AWS: Cost optimization – services expenses overview and traffic costs in AWS Now that we understand what we pay for in AWS, let’s see what… Read More »
We have an API service with Gunicorn in Kubernetes that periodically returns 502, 503, 504 errors. I started debugging it, and found a weird thing: there were no messages in the logs about the received SIGTERM, so I first went to deal with Kubernetes – why doesn’t it send it? The Issue So, here’s what… Read More »
In Kubernetes, in addition to metrics and logs from containers, we can get information about the operation of components using Kubernetes Events. Events usually store information about the status of Pods (creation, evict, kill, ready or not-ready status of pods), WorkerNodes (status of servers), Kubernetes Scheduler (inability to start a pod, etc.). Kubernetes Events types… Read More »
We have an AWS EKS cluster with WorkerNodes/EC2 created with Karpenter. The process of creating the infrastructure, cluster, and launching Karpenter is described in previous posts: Terraform: Building EKS, part 1 – VPC, Subnets and Endpoints Terraform: Building EKS, part 2 – an EKS cluster, WorkerNodes, and IAM Terraform: Building EKS, part 3 – Karpenter… Read More »
I’ve already written a little about Pritunl before – Pritunl: Running a VPN in Kubernetes. Let’s return to this topic again, but this time on EC2 in AWS, without Kubernetes. So, what we need to do is to run some kind of VPN service for the project to have access to Kubernetes APIs/Kubernetes WorkerNodes/AWS RDS/etc… Read More »
Sometimes, when deploying Helm charts, the error “UPGRADE FAILED: another operation (install/upgrade/rollback) is in progress” may appear: It can occur because the previous deployment failed due to errors in the chart, or the connection between the build machine and the Kubernetes cluster was lost. Check the release status with ls –all: $ helm -n dev-backend-api-ns… Read More »
We have a relatively large spending on AWS NAT Gateway Processed Bytes, and it became interesting to know what exactly is processed through it. It would seem that everything is simple – just turn on VPC Flow Logs and see what’s what. But when it comes to AWS Elastic Kubernetes Service and NAT Gateways, things… Read More »
Tracing allows you to track requests between components, that is, for example, when using AWS and Kubernetes we can trace the entire path of a request from AWS Load Balancer to Kubernetes Pod and to DynamoDB or RDS. This helps us both to track performance issues – where and which requests are taking a long… Read More »
Each WorkerNode in a Kubernetes cluster can have a limited number of Pods running, and this limit is determined by three parameters: CPU: the total number of requests.cpu cannot be more than the number of CPUs on the Node Memory: the total number of requests.memory cannot be more than the Memory on the Node IP:… Read More »