Recent Blog Posts

How to fix "Host '' is not allowed to connect" with MySQL Docker

Using the official MySQL Docker image from Docker Hub, I recently ran into the error:

Host '' is not allowed to connect to this MySQL server

The only change I had made to my docker-compose.yml file was:

  image: mysql:5.6
    - '3306'
    # Use this option to persist the MySQL DBs in a shared volume.
    - ./mysqldata:/var/lib/mysql:rw,delegated
    # Use this option to persist the MySQL DBs in a data volume.
    # - db_data:/var/lib/mysql

I switched from using a data volume (db_data) to mounting a volume from my host (mysqldata in the current directory), and after the next time I did a docker-compose down and docker-compose up, I started seeing the error about my host not being allowed to connect to the MySQL server.

Dealing with Drupal 8 and a giant cache_render table

There are a number of scenarios in Drupal 8 where you might notice your MySQL database size starts growing incredibly fast, even if you're not adding any content. Most often, in my experience, the problem stems from a exponentially-increasing-in-size cache_render table. I've had enough private conversations about this issue that I figure I'd write this blog post to cover common scenarios, as well as short and long-term fixes if you run into this issue.

Consider the following scenarios I've seen where a cache_render table increased to 10, 50, 100 GB or more:

DrupalCamp St. Louis 2017 Keynote announcement: Adam Bergstein

DrupalCamp St. Louis 2017 - September 22-23

(It's not too late to submit a session—and register for DrupalCamp soon, since early bird pricing ends on August 1!)

The organizers behind DrupalCamp St. Louis 2017 are happy to announce we have a speaker scheduled to present the Keynote, Adam Bergstein—Associate Director of Engineering at CivicActions!

Adam's Keynote is titled "Restoring Our Lost Imagination", and here's a short summary:

Review: Innergie PowerJoy 30C USB-C Wall Charger

tl;dr: The Innergie PowerJoy USB-C charger is a solid power adapter for charging via USB-C and USB-A simultaneously. If you have a high-power-draw device like a MacBook Pro, then the adapter may have a little less utility, but if you use a smaller USB-C device and need to charge both it and a USB-A device, then this is one of the most compact and well-built adapters I've used.

Innergie PowerJoy 30C USB-C wall power adapter

A month ago, I received an email from Innergie asking me if I'd like to review their new USB-C charger they were releasing. I had just returned from a business trip and was slightly regretting only having my MacBook Pro's included USB-C charger, which has one USB-C port. Charging my phone meant plugging my laptop into the AC adapter, then plugging a Lightning cable into my MacBook Pro.

Fixing MySQL 'The table is full' error using the official MySQL Docker image

Recently I had to test importing some very large databases with lots of giant log tables (e.g. 5+ GB tables), and when I tried doing an import into a local docker MySQL container instance, I got ERROR 1114: The table is full. Here are the commands I used:

# Run a MySQL container locally to test a large file import.
$ docker run --name mysql-import-test -p 3306 -e MYSQL_ROOT_PASSWORD=root -e MYSQL_DATABASE=database_name -d mysql:latest

# Import a database .sql file and monitor progress with pv.
$ pv ~/database.sql | mysql -u root -proot -h --port 32774 database_name
ERROR 1114 (HY000) at line 93898: The table 'xyz' is full

I found that—likely due to some Docker filesystem defaults—the MySQL import would fail every time when there was a database table containing more than 1GB of data. Now, this could be related to the way the database was exported, and I also found some issues where people were using memory tables that got exported and wouldn't import cleanly.


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