AWS EC2 instance user name

When logging into an EC2 instance using SSH, you may receive an error. You check to make sure you have the right instance name, IP address, PEM key etc. but it still fails. You may be using the incorrect user name. The EC2 instance user names by OS are listed here:

http://alestic.com/2014/01/ec2-ssh-username

For example, ubuntu servers are “ubuntu@” amazon is “ec2-user@” and other ones such as Debian are root@

Tunnelbrick not working on MAC

Using this version of Tunnelbrick: Tunnelblick 3.2.9 (build 2891.3328)  -  OpenVPN 2.2.1

The log file kept getting this error: "/sbin/ifconfig tun0 delete

ifconfig: ioctl (SIOCDIFADDR): Can't assign requested address".  This error was in the log file.  I was able to connect to my OpenVPN EC2 instance using VPN but not able to connect to any of the other instances in my VPC.  

The easiest fix is to download Viscosity and use this client product.

CloudFormation access denied error message

In the event you get this message when a CloudFormation script:

AccessDenied. User doesn't have permission to call ec2:RunInstances, this could mean that the AMI is not available or you don't have access to it.  The error is not intuitive.  Check to make sure the AMI exists or if you have access to it.