Category Archives: Troubleshooting

Various problems solutions

Kubernetes: 503 no endpoints available for service – the cause and solution

15 June 2020
 

 We have a Redis service running behind a Service with the ClusterIP type. This Redis must accessible by pods from the same namespace (a Gorush service). The proble is that those pod can’t connect to the Redis service using its gorush-server-redis-svc:6379 name and reporting “Can’t connect redis server: connection refused“: Althought the service is present… Read More »

Docker: configure tzdata and timezone during build

17 May 2020
 

 During a Docker image build – it stops asking to configure the tzdata. Dockerfile at this moment is the next: FROM ubuntu:18.04 RUN apt update && apt install -y python-pip python-dev ssh python-boto3 RUN pip install ansible==2.4.3.0 Let’s reproduce – run the build: And here it hangs waiting for us enter data, and even after… Read More »

Helm: helm-secrets – sensitive data encryption with AWS KMS and use it with Jenkins

16 May 2020
 

 So, as a follow-up to the Helm: Kubernetes package manager – an overview, getting started post – let’s discuss about sensitive data in our Helm charts. What I want is to store a chart files in a repository, but even if such a repo will be a private Github repo – I still don’t want… Read More »

AWS Elastic Kubernetes Service: a cluster creation automation, part 2 – Ansible, eksctl

1 May 2020
 

 The first part – AWS Elastic Kubernetes Service: a cluster creation automation, part 1 – CloudFormation. To remind the whole idea is to create an automation process to create an EKS cluster: Ansible uses the cloudformation module to create an infrastructure by using an Outputs of the CloudFormation stack created – Ansible from a template will… Read More »

Linux: no sound after suspend/sleep – solution

30 April 2020
 

 I have a laptop with Arch Linux. It’s suspended with the systemctl suspend. The issue: after it’s wake up there is no sound. From the information found during the investigation (see links below) the issue happens because of the NVIDIA drivers and isn’t specific to the Arch Linux – can happen with any other Linux… Read More »

Steam: Civilization V, Arch Linux and ERROR:Invalid resolutions constraints: 0x0 must not be greater than 0x0

27 April 2020
 

 I’m using Steam on Arch Linux (see the Arch Linux: Steam installation). And I have Civilization V game here – my favorite game for last N-years. I have NVIDIA drivers installed and most of the games work fine, even World Of Tanks, but I wasn’t able to play Civilization from the moment I’ve installed Steam… Read More »

AWS: eksctl – “Put http://169.254.169.254/latest/api/token: net/http: request canceled”

26 April 2020
 

 We have a Docker image with the eksctl tool included. We also have an ЕС2 with Linux with the eksctl. There is an AWS IAM Instance Profile attached to this EC2 with the AdminAccess policy assigned. On this ЕС2 we have Jenkins running in a Docker container, and it spawns its jobs inside in additional… Read More »

AWS Elastic Kubernetes Service: a cluster creation automation, part 1 – CloudFormation

24 April 2020
 

 The task is: create automation to roll out an AWS Elastic Kubernetes Service cluster from scratch. Will use: Ansible: to automate CloudFormation stack creation and to execute eksctl with necessary parameters CloudFormation with NestedStacks: to create an infrastructure – VPC, subnets, SecurityGroups, IAM-roles, etc eksctl: to create a cluster itself using resources created by CloudFormation… Read More »

Linux: processes core dumps, systemd-coredump and Debian

14 March 2020
 

 Need to get a dump from fro ma PHP process on Debian 9. In this post will take a Linux kernel mechanism to create and manage processes dumps. Kernel’s dumps are created in another way, check Kdump на Arch Wiki. Linux Core Dump The kernel will create a process dump if it performed an invalid… Read More »

Redis: “psync scheduled to be closed ASAP for overcoming of output buffer limits” and the client-output-buffer-limit

26 February 2020
 

 We have a Redis-cluster with Master-slave replication and Sentinel, see the Redis: replication, part 2 – Master-Slave replication, and Redis Sentinel, Redis: fork – Cannot allocate memory, Linux, virtual memory and vm.overcommit_memory, and Redis: main configuration parameters and performance tuning overview posts. The system worked great until we started using it much more actively. Redis… Read More »