Category Archives: Troubleshooting

Various problems solutions

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 »

Linux: PHP-FPM, Docker, STDOUT and STDERR – no an application’s error logs

24 February 2020

 We have a Docker image with NGINX, PHP-FPM, and Supervisor. In the same image, we have our PHP application included, which outputs its errors to the /dev/stderr as per its php.ini file: … [global] error_log=/dev/stderr … The problem is, that if run kubectl logs –  there will be no error output from the application. So,… Read More »

PHP: PHP-FPM ignores environment variables – solutions

19 February 2020

 We have a PHP-based application running in Kubernetes and uses settings from a /app/.env file plus environment variables. The problem is that application running in a Docker container can’t see an $TEST_VAR variable although it’s present in the Deployment: … containers: – name: application-dev-web image: bttrm-application:119 … – name: TEST_VAR valueFrom: secretKeyRef: name: bttrm-app-secret key:… Read More »

Kubernetes: running metrics-server in AWS EKS for a Kubernetes Pod AutoScaler

15 February 2020

 Assuming, we already have an AWS EKS cluster with worker nodes. In this post – we will connect to a newly created cluster, will create a test deployment with an HPA – Kubernetes Horizontal Pod AutoScaler and will try to get information about resources usage using kubectl top. Kubernetes cluster Create a test cluster using… Read More »

Debian: php7.3-curl : Depends: libcurl3 (>= 7.44.0) but it is not installable

23 January 2020

 We have a Jenkins job that runs a Docker container to build a PHP-application based on the Yii framework. Suddenly during the build, we got an error: … Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required… Read More »

KeePass: an MFA TOTP codes, a browser’s passwords, SSH keys passwords storage configuration and Secret Service integration

12 December 2019

 So, this seems to be the last one post in the whole series about passwords and SSH management in Linux. The previous parts were about: Linux: the Nextcloud client, qtkeychain and the “The name org.freedesktop.secrets was not provided by any .service files” error – I found that a keyring service is able to store SSH… Read More »

What is: Linux keyring, gnome-keyring, Secret Service, and D-Bus

7 December 2019

 It’s a really long-read post and I wast sure if it’s better to split it into three parts or put them together. On the one side, there are keyrings, from another – D-Bus, and finally, there is a Secret Service. Eventually, I decided to keep them here together as I googled all it in the… Read More »

Linux: the Nextcloud client, qtkeychain and the “The name org.freedesktop.secrets was not provided by any .service files” error

1 December 2019

 After installing Nextcloud (see the Nextcloud: running in Docker Compose on Debian with Let’s Encrypt SSL post), on the next day its client ton my Arch Linux asked for authentication. But after I entered my credentials, it returned me the following error: Reading from keychain failed with error: ‘The name org.freedesktop.secrets was not provided by… Read More »