Enforcing a least privileged security model can be hard

In a greenfield environment you generally have the luxury to right any wrongs of any past tech debt. It can be more difficult to apply this to an existing environment? For example, my setup is configured to just work with the AWS CLI and various litmus tests to validate that. Generally instructions would include, valid your AWS access.  This can be as simple as: 

$ aws ec2 describe-regions
$ aws ec2 describe-availability-zones --profile oh

As part of documenting some upcoming Athena/Hadoop/Pig/RDBMS posts I decided it was important to separate out the AWS IAM privileges with a new user and permission policies.This introduced a number of steps that simply do not work.  Creating a new AWS IAM user is not complex. Validating console and API access of that user required some revised setup.

$ aws ec2 describe-regions

An error occurred (AuthFailure) when calling the DescribeRegions operation: AWS was not able to validate the provided access credentials

In order to be able to use the CLI you require your aws_access_key_id and aws_secret_access_key information as well as aws_session_token if used. In order for a new individual user to gain this information, you also need a number of policy rules including the ability to ListAccessKeys, CreateAccessKey and potentially DeleteAccessKey.

    "Version": "2012-10-17",
    "Statement": [
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": [
            "Resource": "arn:aws:iam::[account]:user/[username]"

In this example, we also restrict the least privileged model with a specific user resource ARN. For a single user account that is workable, for a large organization it would not.
This gives the ability to configure your AWS CLI via typical ~/.aws/credentials and/or ~/aws/config settings. Performing  the litmus test now gives:

$ aws ec2 describe-regions

An error occurred (UnauthorizedOperation) when calling the DescribeRegions operation: You are not authorized to perform this operation.

This requires a policy of:

    "Version": "2012-10-17",
    "Statement": [
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": [
            "Resource": "*"
$ aws ec2 describe-regions | jq '.Regions[0]'
  "Endpoint": "ec2.eu-north-1.amazonaws.com",
  "RegionName": "eu-north-1",
  "OptInStatus": "opt-in-not-required"

$ aws ec2 describe-availability-zones --filter "Name=region-name,Values=us-east-1" | jq -r '.AvailabilityZones[].ZoneName'


However, this may be too restrictive for a larger organization.  The EC2 Access level for ‘list’ includes currently over 120 individual permissions. A more open policy could be:

    "Version": "2012-10-17",
    "Statement": [
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": [
            "Resource": "*"

However this does not provide all of the EC2 ‘list’ actions, e.g. ExportClientVpnClientConfiguration, and it includes several ‘read’ actions, e.g. DescribeVolumesModifications.
Selecting the ‘list’ tickbox via the GUI will provide all actions by name individually in the policy action list, currently 117, however this is not forward compatible for any future list defined access level actions.

This is before the exercise to starting granting access to a new AWS service – Athena, and its data source S3.

Another reason to avoid RDS

My list of reasons for never using or recommending Amazon’s MySQL RDS service grows every time I experience problems with customers. This was an interesting and still unresolved issue.

ERROR 126 (HY000): Incorrect key file for table '/rdsdbdata/tmp/#sql_5b7_1.MYI'; try to repair it

You may see this is a MyISAM table. The MySQL database is version 5.5, all InnoDB tables and is very small 100MB in total size.
What is happening is that MySQL is generating a temporary table, and this table is being written to disk. I am unable to change the code to improve the query causing this disk I/O.

What I can not understand and have no ability to diagnose is why this error occurs sometimes and generally when the database is under additional system load. With RDS you have no visibility of the server running the production database. While you have SQL access, an API for managing MySQL configuration options (I also add not all MySQL variables), and limited system statistics via a graphical interface, all information about the system performance, disk configuration etc is hidden and not accessible. This is a frustrating limitation of using RDS.

NOTE: While I cannot recommend RDS, I am very happy with AWS EC2 services when correctly configured. For a cloud based MySQL solution I would definitely recommend greater control over your MySQL database using EC2 and EBS.

Basic scalability principles to avert downtime

In the press in the last two days has been the reported outage of Amazon Web Services Elastic Compute Cloud (EC2) in just one North Virginia data center. This has affected many large website includes FourSquare, Hootsuite, Reddit and Quora. A detailed list can be found at ec2disabled.com.

For these popular websites was this avoidable? Absolutely.

Basic scalability principles if deployed in these systems architecture would have averted the significant downtime regardless of your development stack. While I work primarily in MySQL these principles are not new, nor are they complicated, however they are fundamental concepts in scalability that apply to any technology including the popular MongoDB that is being used by a number of affected sites.

Scalability 101 involves some simple basic rules. Here are just two that seem to have been ignored by many affected by this recent AWS EC2 outage.

  1. Never put all your eggs in one basket. If you rely on AWS completely, or you rely on just one availability zone that is putting all your eggs in one basket.
  2. Always keep your important data close to home. When it comes to what is most critical to your business you need access and control to your information. At 5am in the morning when the CEO asks how long will our business be unavailabla and what is needed to resolve the problem, the answer “We have no control over this and have no ETA” is not an acceptable answer.

With a successful implementation and appropriate data redundancy you may not have an environment immediately available however you have access to your important information and the ability to create one quickly. Many large hosting companies can provide additional H/W on near demand, especially if you have an initial minimal footprint. Indeed using Amazon Web Services (AWS) as a means to avert a data center disaster is an ideal implementation of Infrastructure As A Service (IAAS). Even with this issue, organizations that had planned for this type of outage could have easily migrated to another AWS availability zone that was unaffected.

Furthermore, system architecture to support various levels of data availability and scalability ensure you can handle many more various types of unavailability without significant system down time as recently seen. There are many different types of availability and unavailability, know what your definition of downtime is and supporting disasters should be your primary focus of scalability, not an after thought.

As an expert in performance and scalability I can help your organization in the design of a suitable architecture to support successful scalability and disaster. This is not rocket science however many organizations gamble without the expertise of a professional to ensure business viability.

Problems compiling MySQL 5.4

Seem’s the year Sun had for improving MySQL, and with an entire new 5.4 branch the development team could not fix the autoconf and compile dependencies that has been in MySQL for all the years I’ve been compiling MySQL. Drizzle has got it right, thanks to the great work of Monty Taylor.

I’m working on the Wafflegrid AWS EC2 AMI’s for Matt Yonkovit and while compiling 5.1 was straight forward under Ubuntu 8.10 Intrepid, compiling 5.4 was more complicated.

For MySQL 5.1 I needed only to do the following:

apt-get install -y build-essential
apt-get install libncurses5-dev
make install

For MySQL 5.4, I elected to use the BUILD scripts (based on Wafflegrid recommendations). That didn’t go far before I needed.

apt-get install -y automake libtool

You then have to go compiling MySQL 5.4 for 10+ minutes to get an abstract error, then you need to consider what dependencies may be missing.
I don’t like to do a blanket apt-get of a long list of proposed packages unless I know they are actually needed.

The error was:

make[1]: Entering directory `/src/mysql-5.4.0-beta/sql'
make[1]: warning: -jN forced in submake: disabling jobserver mode.
/bin/bash ../ylwrap sql_yacc.yy y.tab.c sql_yacc.cc y.tab.h sql_yacc.h y.output sql_yacc.output -- -d --verbose
make -j 6 gen_lex_hash
make[2]: Entering directory `/src/mysql-5.4.0-beta/sql'
rm -f mini_client_errors.c
/bin/ln -s ../libmysql/errmsg.c mini_client_errors.c
make[2]: warning: -jN forced in submake: disabling jobserver mode.
rm -f pack.c
../ylwrap: line 111: -d: command not found
/bin/ln -s ../sql-common/pack.c pack.c
make[1]: Leaving directory `/src/mysql-5.4.0-beta/sql'
make: *** [all-recursive] Error 1

What a lovely error ../ylwrap: line 111: -d: command not found

ylwrap is part of yacc, and by default in this instance it’s not even an installed package. I’ve compiled MySQL long enough that it requires yacc, and actually bison but to you think it would hurt if the configure told the user this.

It’s also been some time since I’ve compiled MySQL source, rather focusing on Drizzle. I had forgotten just how many compile warnings MySQL throws. Granted a warning is not an error, but you should not just ignore them in building a quality product.

Announcing Drizzle on EC2

I have published the very first sharable Drizzle Amazon Machine Image (AMI) for AWS EC2, based on the good feedback from my discussion at the Drizzle Developer Day on what options we should try.

This first version is a 32bit Developer instance, showcasing Drizzle and all necessary developer tools to build Drizzle from source.

What you will find on drizzle-ami/intrepid-dev32 – ami-b858bfd1

Ubuntu 8.10 Intrepid 32 bit base server installation:

  • build tools
  • drizzle dependencies
  • bzr 1.31.1

From the respective source trees the following software is available:

  • drizzle 2009.04.997
  • libdrizzle 0.0.2
  • gearman 0.0.4
  • memcached 1.2.8
  • libmemcached 0.28

Drizzle has been configured with necessary dependencies for PAM authentication, http_auth, libgearman and MD5 but these don’t seem to be available in the binary distribution.

I will be creating additional AMI’s including 64bit and LAMP ready binary only images.

The following example shows using drizzle on this AMI. Some further work is necessary for full automation, parameters and logging. I’ve raised a number of issues the Drizzle Developers are now hard at work on.

1. Starting Drizzle

ssh ubuntu@ec2-xxx-xxx-xxx-xxx.compute-1.amazonaws.com
sudo /etc/init.d/drizzle-server.init start &

2. Testing Drizzle (the sakila database has been installed)

$ drizzle
Welcome to the Drizzle client..  Commands end with ; or g.
Your Drizzle connection id is 4
Server version: 2009.04.997 Source distribution

Type 'help;' or 'h' for help. Type 'c' to clear the buffer.

drizzle> select version();
| version()   |
| 2009.04.997 |
1 row in set (0 sec)

drizzle> select count(*) from sakila.film;
| count(*) |
|     1000 |
1 row in set (0 sec)

3. Compiling Drizzle

sudo su - drizzle
deploy  drizzle  libdrizzle  sakila-drizzle
cd drizzle
./configure --help
Description of plugins:

   === HTTP Authentication Plugin ===
  Plugin Name:      auth_http
  Description:      HTTP based authentications
  Supports build:   static and dynamic

   === PAM Authenication Plugin ===
  Plugin Name:      auth_pam
  Description:      PAM based authenication.
  Supports build:   dynamic

   === compression UDFs ===
  Plugin Name:      compression
  Description:      UDF Plugin for compression
  Supports build:   static and dynamic
  Status:           mandatory

   === crc32 UDF ===
  Plugin Name:      crc32
  Description:      UDF Plugin for crc32
  Supports build:   static and dynamic
  Status:           mandatory

   === Error Message Plugin ===
  Plugin Name:      errmsg_stderr
  Description:      Errmsg Plugin that sends messages to stderr.
  Supports build:   dynamic

   === Daemon Example Plugin ===
  Plugin Name:      hello_world
  Description:      UDF Plugin for Hello World.
  Supports build:   dynamic

   === Gearman Logging Plugin ===
  Plugin Name:      logging_gearman
  Description:      Logging Plugin that logs to Gearman.
  Supports build:   dynamic

   === Query Logging Plugin ===
  Plugin Name:      logging_query
  Description:      Logging Plugin that logs all queries.
  Supports build:   static and dynamic
  Status:           mandatory

   === Syslog Logging Plugin ===
  Plugin Name:      logging_syslog
  Description:      Logging Plugin that writes to syslog.
  Supports build:   static and dynamic
  Status:           mandatory

   === MD5 UDF ===
  Plugin Name:      md5
  Description:      UDF Plugin for MD5
  Supports build:   static and dynamic

   === One Thread Per Connection Scheduler ===
  Plugin Name:      multi_thread
  Description:      plugin for multi_thread
  Supports build:   static
  Status:           mandatory

   === Old libdrizzle Protocol ===
  Plugin Name:      oldlibdrizzle
  Description:      plugin for oldlibdrizzle
  Supports build:   static
  Status:           mandatory

   === Pool of Threads Scheduler ===
  Plugin Name:      pool_of_threads
  Description:      plugin for pool_of_threads
  Supports build:   static
  Status:           mandatory

   === Default Signal Handler ===
  Plugin Name:      signal_handler
  Description:      plugin for signal_handler
  Supports build:   static
  Status:           mandatory

   === Single Thread Scheduler ===
  Plugin Name:      single_thread
  Description:      plugin for single_thread
  Supports build:   static
  Status:           mandatory

   === Archive Storage Engine ===
  Plugin Name:      archive
  Description:      Archive Storage Engine
  Supports build:   static
  Status:           mandatory

   === Blackhole Storage Engine ===
  Plugin Name:      blackhole
  Description:      Basic Write-only Read-never tables
  Supports build:   static and dynamic
  Configurations:   max, max-no-ndb

   === CSV Storage Engine ===
  Plugin Name:      csv
  Description:      Stores tables in text CSV format
  Supports build:   static
  Status:           mandatory

   === Memory Storage Engine ===
  Plugin Name:      heap
  Description:      Volatile memory based tables
  Supports build:   static
  Status:           mandatory

   === InnoDB Storage Engine ===
  Plugin Name:      innobase
  Description:      Transactional Tables using InnoDB
  Supports build:   static and dynamic
  Configurations:   max, max-no-ndb
  Status:           mandatory

   === MyISAM Storage Engine ===
  Plugin Name:      myisam
  Description:      Traditional non-transactional MySQL tables
  Supports build:   static
  Status:           mandatory

Report bugs to <http://bugs.launchpad.net/drizzle>.

Extending application data to the cloud

I was one of the invited panel speakers to A panel on Cloud Computing this week in New York. As one of 2 non vendor presenters, it was a great experience to be invited and be involved with vendors.

While I never got to use my slides available here, I did get to both present certain content, and indeed questions and discussions on the night were on other points of my content.

Cloud computing is here, it’s early days and new players will continue to emerge. For example, from the panel there was AppNexus, reviewed favorably at Info World in comparison with EC2 and Google App Engine, 10gen, an open source stack solution and Kaavo which from an initial 60 seconds of playing provide a management service on top of AWS similar to what ElasticFox provides. I need to investigate further how much the feature set extends and would compete with others like RightScale for example.

The greatest mystery came from Hank Williams and his stealth Kloudshare. He did elaborate more on where they aim to provide services. A new term discussed was “Tools as a service”, akin to moving use metaphorically from writing in Assembly language to the advanced frameworks of today’s generation of languages such as Java and Ruby.

Thanks to Murat Aktihanoglu of Unype who chaired the event.

Your data and the cloud

I will be speaking on July 29th in New York at an Entrepreneurs Forum on A Free Panel on Cloud Computing. With a number of experts including Hank Williams of KloudShare, Mike Nolet of AppNexus, and Hans Zaunere of New York PHP fame is should be a great event.

The focus of my presentation will be on “Extending existing applications to leverage the cloud” where I will be discussing both the advantages of the cloud, and the complexities and issues that you will encounter such as data management, data consistency, loss of control, security and latency for example.

Using traditional MySQL based applications I’ll be providing an approach that can lead to your application gaining greater power of cloud computing.

About the Author

Ronald Bradford provides Consulting and Advisory Services in Data Architecture, Performance and Scalability for MySQL Solutions. An IT industry professional for two decades with extensive database experience in MySQL, Oracle and Ingres his expertise covers data architecture, software development, migration, performance analysis and production system implementations. His knowledge from 10 years of consulting across many industry sectors, technologies and countries has provided unique insight into being able to provide solutions to problems. For more information Contact Ronald.

Setting up on EC2

Thanks to my friend Dustin, and his EC2 demo using Elasticfox Firefox Extension for Amazon EC2 I got an EC2 image setup. With other references Link 1,Link 2,Link 3 I was also able to create my own AMI.

Some notes specific for my configuration.

Pre-config ElasticFox key for launching directly from ElasticFox SSH connections.

mkdir ~/ec2-keys
mv ~/Downloads/elasticfox.pem ~/ec2-keys/id_elasticfox
chmod 600 ~/ec2-keys/id_elasticfox
chmod 700 ~/ec2-keys/
ssh -i /Users/rbradfor/ec2-keys/id_elasticfox root@ec2-99-999-999-999.compute-1.amazonaws.com

Installed Software.

apt-get update
apt-get -y autoremove
apt-get -y install apache2
apt-get -y install mysql-server
# Prompts for password (very annoying)
apt-get -y install php5
apache2ctl graceful
echo "Hello World" > /var/www/index.html
echo "< ? phpinfo() ?>" > /var/www/phpinfo.php

Configuration to save AMI.

scp -i ~/ec2-keys/id_elasticfox ~/ec2-keys/id_elasticfox pk-CHK7DP4475BWUKIUF4WFDIW3VMYDYOHQ.pem cert-CHK7DP4475BWUKIUF4WFDIW3VMYDYOHQ.pem root@ec2-99-999-999-999.compute-1.amazonaws.com:/mnt
ec2-bundle-vol -d /mnt -c cert-CHK7DP4475BWUKIUF4WFDIW3VMYDYOHQ.pem -k pk-CHK7DP4475BWUKIUF4WFDIW3VMYDYOHQ.pem -u AccountNumber -r i386 -p ubuntu804_lamp
ec2-upload-bundle -b rbradford_804_lamp_ami -m /mnt/ubuntu804_lamp.manifest.xml -a AccessID -s SecretKey