Comment 2 for bug 863510

The relevant WTF output can be seen here:

http://wtf.labix.org/370/ec2-wordpress.out.FAILED

+++ juju destroy-environment
2011-09-29 22:46:08,163 INFO Destroying environment 'sample' (type: ec2)...
2011-09-29 22:46:09,966 INFO Waiting on 3 EC2 instances to transition to terminated state, this may take a while
Unhandled error in Deferred:
Unhandled Error
Traceback (most recent call last):
Failure: twisted.internet.defer.TimeoutError: Getting https://ec2.us-east-1.amazonaws.com/?AWSAccessKeyId=AKIAJK3WYEWHCTYQBF7A&Action=DeleteSecurityGroup&GroupName=juju-sample-1&Signature=hIEGPhSpPtdir4raEbDPwUjoyAdTtrZaePnYrqu0urU%3D&SignatureMethod=HmacSHA256&SignatureVersion=2&Timestamp=2011-09-30T02%3A46%3A45Z&Version=2008-12-01 took longer than 30 seconds.
WARNING: this command will destroy the 'sample' environment (type: ec2).
This includes all machines, services, data, and other resources. Continue [y/N]Exception RuntimeError: 'generator ignored GeneratorExit' in <generator object destroy_environment at 0x35430f0> ignored

It looks like this issue is more problematic than the snippet reported with the bug: the Twisted reactor ignored the error here, and thus hangs forever. Making the control Commander more robust should fix this and other issues.