S3 Access Denied: AI SRE Agent Debugs Lambda Permissions
The bucket is right there and the function still cannot read it. AURA reads the failure, names the one missing action, and returns the policy to add.
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A permissions failure gives you the symptom and not the action name. The usual path is reading the error, guessing which actions the execution role is short, and widening the policy until the call goes through.
Greg hands AURA a Lambda function that fails when it tries to reach an S3 bucket. AURA identifies the missing ListBucket permission on that particular bucket and returns the minimum policy needed to allow it.
Greg adds the suggested policy, ListBucket and GetObject, to the role the Lambda function runs as, saves it, and runs the function again. The response comes back with the full file listing and 11 items retrieved.
AURA recommends here and does not act. The policy change is made by hand on the execution role, and nothing in this run gives AURA write access to IAM. Greg also notes that AURA can be configured with multiple agents working as a team, which other videos cover rather than this one.
AURA is built for SREs and cloud engineers who need the exact permission a failing function is missing without widening the role to find out.
0:00 A Lambda that cannot read its S3 bucket
0:21 Handing the failure to AURA
0:49 More complex AWS problems and multi-agent setups
1:38 The finding: a missing ListBucket permission
2:03 Adding the minimum policy to the execution role
2:42 Rerunning the function and confirming 11 files
#AURA #S3 #AISRE
Transcript
A Lambda that cannot read its S3 bucket
0:00 Hello, this is Greg from Mezmo. Today I will be showing you AURA and its ability to help me with another AWS problem. Today I have a problem where I created a Lambda function that does not have the proper permissions to get to my S3 bucket.
Handing the failure to AURA
0:21 As you can see here, I don't have the proper permissions, so we're going to have AURA help us with it.
More complex AWS problems and multi-agent setups
0:49 Obviously this is a very simple example, but AURA can help you with more complex examples and problems in your AWS environment. You can also, as shown in other videos here and on our online guides, configure AURA in such a way that you have multiple agents working together as a team, to resolve problems in your environment.
The finding: a missing ListBucket permission
1:38 So as you can see here, it found that we're missing the ListBucket permission on my particular bucket. And it will give us down here the minimum policy that we would need, to allow that.
Adding the minimum policy to the execution role
2:03 So we're going to go ahead and add this policy that it suggests, which is actually ListBucket and GetObject, so I've gone into the role that my Lambda function is running as, and now we're going to go ahead and save that out.
Rerunning the function and confirming 11 files
2:42 And then we will try and run our Lambda function again. And now we'll see if we get our response, and we do. We get all of our files listed, successfully retrieved 11 items, and we're showing all the files that are in my bucket. Thanks.
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