The Cities: Skylines game keeps objects in memory even if the object is not used. Even a 16GB system can crash frequently if the memory usage is not managed. “Oops! The game crashed The memory usage is high, even when the map is not too complex. Enable enough Virtual Memory Make sure Windows has enough …
Author Archives: Laszlo Pinter
Get jstack and other Java utilities without installing the Java JDK
Open a Windows command prompt Create a directory for the volume and start the openjdk container In the Java container copy the contents of the Java bin directory to the mapped volume
Docker in Windows 10 via VMware Fusion on a MacBook Pro
To run Windows Docker containers on your Macintosh computer, use the following setup. This will introduce a performance hit, because you run virtualization in virtualization. Besides the usual setup process, you need to enable hypervisor applications to avoid the error Error response from daemon: container … encountered an error during CreateContainer: failure in a Windows …
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Turn off the GDPR cookie notification in a dotnet core MVC web application
The dotnet core MVC web application template adds the GDPR cookie acceptance message to the header of the page template. When the site is hosted with HTTP the accept button does not clear the message resulting an infinite loop, when the user cannot log in and the site continuously asks for the acceptance. When the …
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Read the database connection string and other secrets from environment variables
It is not good practice to store secrets in the source code repository. The sample C# dotnet core application code stores the database connection string in the appsettings.json file which eventually will be pushed into GitHub. To follow the Twelve-Factor App methodology, store the configuration values in environment variables and load them runtime. This method …
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Mount NFS volume from macOS
When we try to mount an NFS with from macOS we get the error message: docker: Error response from daemon: error while mounting volume ‘/var/lib/docker/volumes/…/_data’: failed to mount local volume: mount :/data:/var/lib/docker/volumes/…/_data, data: addr=…,vers=4: operation not permitted. or docker: Error response from daemon: error while mounting volume ‘/var/lib/docker/volumes/…/_data’: failed to mount local volume: mount :/data:/var/lib/docker/volumes/…/_data, …
ERROR: column “…” does not exist
PostgreSQL internally converts all column and table names to lowercase when executing the SQL query. If the column or table name contains uppercase letters, we need to use double quotes to be able to reference them. When we get the error message ERROR: column “username” does not exist select * from public.”AspNetUsers” where UserName = …
PostgreSQL management tools
Install postgresql The postgresql package contains the PostgreSQL utilities: psql, pg_dump On macOS Install pgAdmin pgAdmin is a browser based database management tool for PosgtreSQL databases. Download Download the installer from https://www.pgadmin.org/download/ Install On macOS Double click the downloaded file Accept the license agreement Drag the application into the Applications folder Start pgAdmin On macOS …
syntax error, unexpected tLABEL in Chef Test Kitchen
During the test of a Chef recipe that contains a template we may encounter the error message syntax error, unexpected tLABEL MY_KEY: MY_VALUE Make sure there is no white space between the keyword variables and the opening parenthesis in the template definition:
How to remove all Docker containers and images from the host
Docker images are stored on the host to launch as fast as possible. The drawback is, Docker can fill the hard drive with unused images. A recent possible bug in Docker caused the accumulation of unused, unreferenced images on the host. To delete all Docker containers and images, use these commands in the terminal Get …
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