AWS-CLI – IAM Role Fails – “Unable to locate credentials”

If you run a bootstrap script that uses AWS CLI, you’ve probably run into an intermittent fatal error that says, “Unable to locate credentials”. IAM Roles should just work on the instance, but the credentials are not reliable in my experience on Linux systems. Before I attempt to run any bootstrap script, I use the following code to ensure the IAM credentials are where they should be.

config_exists=$(aws configure list | grep access_key | grep iam-role);
until [ ! -z "$config_exists" ]; do echo 'Amazon is playing games here. Trying to get IAM creds that should already be here ...'; sleep 2; config_exists=$(aws configure list | grep access_key | grep iam-role); done;

Get Latest Project Build from CodeBuild on Single EC2 Instance

If you are bootstrapping a new instance into your cluster, you probably don’t want to kick off an entire deployment pipeline to get the latest build onto just that one instance. I grab the latest build from CodeBuild S3 artifact storage and untar it right into the pertinent path. It’s a much quicker bootstrap and doesn’t take any other instance out of commission for a deployment. Note: This requires the jq package for parsing the response JSON.

LOCATION=$(aws codebuild batch-get-builds --ids $(aws codebuild list-builds-for-project --project-name $PROJECT | jq -r '.ids[0]') | jq -r '.builds[].artifacts.location' | sed 's/arn\:aws\:s3\:\:\:/s3:\/\//g')
tar -xvf $LOCATION

Why does RDS MySQL use so much storage?

We recently migrated 23GB of data from an EC2 MySQL database server to RDS. During the migration, we noticed that the free storage on the 100GB instance was being eaten up quickly. It took some digging to find out that AWS does some configuration trickery here to make more money from unsuspecting customers, in my opinion. They set innodb_file_per_table to true by default.This creates a file per table in the database instead of one global tablespace. There’s really no benefit that I’ve found for performance by doing this. It’s a clever way for users who have file access to migrate tables individually instead of entire databases. The key here is that there is no SSH access for RDS, so, why do we need a file per table? It doesn’t make sense if we can’t even use the feature for its original purpose.

Horizontally scalable on AWS ELB ALB (with HTTPS)

Setting up a horizontally scalable stack to work with AWS ELB can be extremely frustrating as there are several moving parts. There’s also a lot of outdated documentation about AWS ELB that doesn’t include the new Application Load Balancer setup. Here’s a simple setup for getting started with using behind an ELB using HTTPS.

WordPress Data Migration with MySQL

WP-CLI is a great tool for migrating data within WordPress from the command line, however it’s not always the appropriate or most efficient way to move data around. My rule of thumb is if I am working with unserialized data, I try to use MySQL queries first.

A simple migration script with WP-CLI could take up a lot of I/O and could take minutes or hours to complete depending on the data set. The same query in MySQL can take mere seconds. For example, if you wanted to take meta values from a specific post type, and move them to a new key, the WP-CLI script might look something like this:


Installing WordPress and HHVM on Heroku For Beginners

For someone not familiar with Heroku, it can be a bit daunting to get WordPress and HHVM running on a Heroku web dyno after working on a traditional LAMP stack. That’s why I titled this for beginners because I are one and it took me a while to wrap my head around it. Let me also say that I am not a Heroku master and this tutorial most certainly will be agnostic of some of the more technical aspects of Heroku.

This tutorial is also just a means to get WordPress running on a single dyno (server) using the free tier and has not been tested on an enterprise installation. As a point-of-reference, though technically savvy, I do not use because the template they use has actual distribution code committed to the repo which relies on a human to continually update. At this reading, some of the plugins are out-of-date, and I prefer to pull distributions from the source using Composer.


Redirect www to non-www via DNS

Apps rise and fall on single characters. One misplaced character can tank ten thousand lines of code. The same is true with URL redirection. Most DNS providers have a GUI for redirecting URLs. I’ve learned the hard way that the forward slash character is of utmost importance when using these features. For example, if I want to forward all www traffic to (sans slash), all of my traffic for www will end up only on my homepage which is no good for SEO, analytics, user experience, etc…. If I want the DNS provider to forward the entire request, I have to have a trailing slash (

Using HTTP Auth Basic in WordPress

I was posed with the question as to how to protect a BB forum with a general user/pass for students at a community college. Since the segment that needed securing was not a standard post, but a custom rewrite, there was no way to use the native post password feature. Using .htaccess was also out as that protects entire directories.

Fortunately, PHP allows you to implement auth headers to handle this. Let me first say that I understand that HTTP Auth Basic is not a secure authentication solution, but it is a privacy gate which is all that was requested to help reduce spam, malicious posts, etc.. With the proper hooks, I was able to target the specific URI segment and it worked like a charm.


Find all sites on server by IP address

I don’t advocate using the following to hack other sites. I found it interesting that my host was serving pornography from the same box I was using, so I switched to my own cloud server. There are two ways to go about finding other sites on your server. If you don’t know your server IP, you can search


and there are plenty of sites that will expose the server domain.

Bing IP Search

This seems to be pretty reliable and up-to-date. Bing has an IP operator that allows you to specify an IP address when searching.

Example Search:


Hackers will use this operator to find sites running WordPress using the images tab. Once they identify several domains, they can easily ascertain your WP version with the generator meta tag. A hacker can know all of the WordPress installations and versions of those sites without leaving a probing footprint. If there is a known vulnerability with one of your versions, it’s a cinch to attack it. Keep your software up-to-date and your back-doors closed friends. Bing is not your friend with this horrid search operator.

Example Search:

ip: wp-content