How to iterate through all aws region to get security group info

Question

I am unable to iterate through the list of AWS regions that i provided & i am confused why the list is starting from reverse order?

This code basically connects through all aws regions one by one and then prints the security group details :

regions = ['us-east-1','us-west-1','us-west-2','eu-west-1','sa-east-1','ap-southeast-1','ap-southeast-2','ap-northeast-1']
for region in regions:
  connection=ec2.connect_to_region(region)
  sg.extend(connection.get_all_security_groups())


def getTag(instanceId):

    reservations=connection.get_all_instances(filters={'instance_id':instanceId})
    for res in reservations:
        for instance in res.instances:
            return instance.tags['Name'],instance.private_ip_address,instance.region

try:

    for securityGroup in sg:
       for rule in securityGroup.rules:
           global instanceId;
           if rule.to_port == '22'  and '0.0.0.0/0' in str(rule.grants):
                for instanceid in securityGroup.instances():
                   instanceId=str(instanceid)
                   print "Port 22 is open for 0.0.0.0/0:, SecurityGroupName: %s  Instance Details --> : %s " %(securityGroup.name,  getTag(instanceId.split(':')[1]))

Based on the answer , I am now unable to get instance details, the result is

Port 22 is open for 0.0.0.0/0:, SecurityGroupName: interview-linux  Instance Details --> : None 
Port 22 is open for 0.0.0.0/0:, SecurityGroupName: interview-linux  Instance Details --> : None 
Port 22 is open for 0.0.0.0/0:, SecurityGroupName: launch-wizard-mingjun  Instance Details --> : None 
Port 22 is open for 0.0.0.0/0:, SecurityGroupName: SSH+HTTPS  Instance Details --> : None 
Port 22 is open for 0.0.0.0/0:, SecurityGroupName: temp-engg-logi  Instance Details --> : None 
Port 22 is open for 0.0.0.0/0:, SecurityGroupName: na-prod-1w-secgroup  Instance Details --> : None 
Port 22 is open for 0.0.0.0/0:, SecurityGroupName: na-prod-1w-secgroup  Instance Details --> : None 
Port 22 is open for 0.0.0.0/0:, SecurityGroupName: na-trial-1w-secgroup  Instance Details --> : None 
Port 22 is open for 0.0.0.0/0:, SecurityGroupName: na-trial-1w-secgroup  Instance Details --> : Non

Answer 1

Because in your for region in regions: loop you are overwriting sg in each iteration. What you probably want is

sg = list()
for region in regions:
  connection=ec2.connect_to_region(region)
  sg.extend(connection.get_all_security_groups())

Edit: (Instance Details --> : None)

The problem here is, in the loop I mentioned earlier, you are overwriting connection too ie connection=ec2.connect_to_region(region) .

So when you do connection.get_all_instances(filters={'instance_id':instanceId}) in your getTag method, instanceId is looked for only in the last region ie ap-northeast-1 . As the instance does not belong to this region, so you get None .

You need to reorder your code to something like

def getTag(connection, instanceId):
    reservations=connection.get_all_instances(filters={'instance_id':instanceId})
    for res in reservations:
        for instance in res.instances:
            return instance.tags['Name'],instance.private_ip_address,instance.region

regions = ['us-east-1','us-west-1','us-west-2','eu-west-1','sa-east-1','ap-southeast-1','ap-southeast-2','ap-northeast-1']
for region in regions:
    connection=ec2.connect_to_region(region)
    sg = connection.get_all_security_groups()
    try:
        for securityGroup in sg:
           for rule in securityGroup.rules:
               if rule.to_port == '22'  and '0.0.0.0/0' in str(rule.grants):
                   for instanceid in securityGroup.instances():
                       instanceId=str(instanceid)
                       print "Port 22 is open for 0.0.0.0/0:, SecurityGroupName: %s  Instance Details --> : %s " %(securityGroup.name,  getTag(connection, instanceId.split(':')[1]))