Category: aws

Blog posts talking about stuff around AWS.

Grab the Network wheel, our SGs & NACLs are 2-trackin!

by EarpMoonWater, posted in aws

Goal:

Uhh-ohh, we let the newbie drive & were off the road… lets take a peak under the hood & see why we can’t connect to the internet. We understand why an instance cant connect to internet. This post should share an order of operations if one does not know why an instance is not connecting to the internet.

Lessons Learned:

  • Determine why instance cant connect to internet
  • ID issues preventing instances from connecting to the internet
  • Important Notes:
    • We have 3 VPCs w/SSH connection & NACLs configured through route table
    • Instance 1 & 2 have connection to internet & are a-okay…
    • Instance 3 is not connected to the internet, so we outtah’ figure out the problem.

Order of Operations:

  • Instance
  • Security Group
  • Subnet
  • NACL
  • Route table
  • Internet gateway

Solution:

  • Instance
    • No public IP address
  • NACL
    • Deny rules for inbound & outbound that prevents all pinging & traffic to instance
  • Route Table
    • Did not have route to internet gateway

Determine why instance cant connect to internet:

Instance:

  • Start w/networking & manage IP address
    • See no public IP address below in screenshot
  • Wham bam thank ya mam! Fixed!… Wait, it isn’t?

Security Group:

  • Can we ping the instance?
  • Remember when looking at rules, just cuz says private – doesn’t mean it is! So check the inbound/outbound rules details

PING!

  • Nothing. Okay, I reckon to keep lookin..

Subnet:

  • Look at private IP address & then VPC
    • Specifically under subnets pay attention to the VPC ID
  • Looks okay so far, keep on keepin on!

NACLs:

  • We found the issue!! The NACL rules deny all inbound/outbound traffic into the instance!
    • Even tho the security group does allow traffic, remember the order of operations from in-to-out..

PING!!

  • Still nothing, hmm..

Route Table:

  • Ah-ha! We found the issue…again!
    • There is no route to the internet gateway

ID issues preventing instances from connecting to the internet:

Instance:

  • Allocate an Elastic IP Address, not a public one!!

NACLs:

  • The options we have are:
    • Change the NACL security rules
    • Get a different NACL w/proper rules in it
      • In prod… dont do this cuz it can affect all the subnets inside of it.
  • Under public-subnet4 (which was the original VPC ID we had for instance 3), select edit network ACL association, & change to the NACL to the public-subnet3

Route Tables:

  • The options we have are:
    • Add a route to the table that allows traffic to flow from subnet to internet gateway
      • Remember in other environments, there maybe others using this route table only permitting private access, so not modify.
    • Select route table that has appropriate entries
  • Here we edit the route table association & then notice the difference in the route table permitting connection/traffic

Ping!

  • YEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEET!!
  • Now if you desired you can SSH into the instance

<Event>Bridge the SNS & CloudWatch gap!

by EarpMoonWater, posted in aws

Goal:

Lets <Event>Bridge the gap for SNS email notifications to trigger an alarm to stop an EC2 & check the CloudWatch logs

Lessons Learned:

  • Create SNS & add email address
  • Create Amazon EventBridge rule to trigger SNS when EC2 state changes
  • Change state of EC2 & verify change in CloudWatch logs from a SNS notification

Create SNS & add email address:

Create Amazon EventBridge rule to trigger SNS when EC2 state changes“

    Change state of EC2 & verify change in CloudWatch logs from a SNS notification:

    Ditch the click-opps w/CLI & Lambda

    by EarpMoonWater, posted in aws

    Goal:

    Click-Opps is old school! Have you ever thought what it be like to get out of the console & use CLI to create a Lambda function! During this we’ll check CloudWatch to see whats going on!

    Lessons Learned:

    • Create Lambda function using AWS CLI
    • Check CloudWatch logs

    SSH:

    • Create 2 S3 buckets & EC2, after that utilize IP address for SSH login
    • To ensure AWS is installed properly, conduct the following commands
      • aws help
      • aws lambda help

    Create & Invoke Function using AWS CLI:

    • After ensuring you lambda can be located in the S3 bucket region you located it, vim the file, next zip it.
    • Create & Update your function
    • Invoke your function

    Check CloudWatch Logs:

    • Wallah, alas.

    Lamb<da>s in the AMAZON!? (..SQS)

    by EarpMoonWater, posted in aws

    Goal:

    W/magic I will make this message appear!…. or just use a Lambda function that is triggered using SQS & input data into a DB.

    Lessons Learned:

    • Create Lambda function
    • Create SQS trigger
    • Copy source code into Lambda function
    • Go to console for the EC2 & test the script
    • Double check messages were placed into the DB

    Create Lambda function:

    • 3 minor details to utilize:
      • Name = SQS DynamoDB
      • Use = Python 3.x
      • Role = lambda-execution-role
    • Alright, whew – now thats over w/it….

    Create SQS trigger:

    • Are you triggered bro? Hopefully “SQS” & “Messages” trigger you…
      • Important note – create a SQS message, so when creating the trigger – you can snag that message created in SQS

    Copy source code into Lambda function:

    • Copy-n-pasta into the lambda_function.py…. now destroy .. ahem, DEPLOY HIM!!

    Go to console for the EC2 & test the script:

    • Sign your life away & see what the damage is! (aka: go to your EC2 instance)

    Double check messages were placed into the DB

    • After you checked EC2, lets double… quadruple? You checked it 1x, so your checking 2x? Or is it multiples of 4?.. idk regardless, you can look at your DB to see if you have a message from Lambda. Have at it.
      • Below is what SQS & Dynamo DB prolly looks like

    Wanna Monitor a CloudFormation stack w/AWS Config?

    by EarpMoonWater, posted in aws

    Goal:

    Lets see how to use AWS Config to monitor if EC2 instances that are launched comply w/the instance types specified in AWS Config

    Lessons Learned:

    • Create AWS Config Rule
    • Make EC2 instance compliant w/config rule

    Create AWS Config Rule:

    • You will see a couple json files, grab the 2nd one “badSG”
    • Create a key-pair
    • Example of the issue in the CloudFormation Stack
    • Here you can see we only say “securitygroups” – – – not, “SecuritygroupIDs”.
      • Easy fix, once you find it in the documentation.

    Create new stack for updated SG:

    • Go ahead & post the 3rd json file in the “infrastructure composer” under CloudFormation
    • Like before go get your subnet, SG, & VPC IDs

    Make EC2 instance compliant w/config rule:

    • Snag the 1st json file in the CloudFormation github link
    • Go to AWS Config
    • Now create a new stack for config record
    • Now your stack is created – wow.
    • Jump back to AWS Config to see your rules, are you compliant?
      • If not, re-upload your CloudFormation template depending what your AWS Config found
        • Example
          • EC2 instance non-compliant
    • Now what? Well delete whatever is not in use. OR don’t & see your bills pile up!

    Updating your goodies in CloudFormation Stacks

    by EarpMoonWater, posted in aws

    Goal:

    Wanna see what happens when one can update CloudFormation stacks w/direct updates & use change sets to update the stack? Well sit back & watch the show.

    Lessons Learned:

    • Deploy a stack using AWS CloudFormation Templates
    • Update stack to scale up
    • Update stack to scale out

    Deploy a stack using AWS CloudFormation Templates:

    • After downloading the stack, go create key pair. What are you waiting for? Go, quick, run, go!
    • Remember the slick view one can peer into?!
    • Hope your stackin like this?

    Update stack to scale up:

    • Yeah, you know what to do. Update the stack EC2 instance to medium. Just do it.
    • To double-check your work, snag that http above in “value”.
      • See the same test page below!?

    Update stack to scale out:

    • Lastly snag that bottom yaml file & re-upload into your stack #CHAAAAANGE
    • Difference here is we have 2 new instances added
    • Scroll to bottom of seeing the summary of changes
    • And like before, see the changes happening live!
      • I know, fancy – ooooo ahhhh

    Play Detective w/CloudFormation

    by EarpMoonWater, posted in aws

    Goal:

    Configuration draft is like poetry, & everyone hates poetry…Cloudformation can assist in bringing the stack back in sync to the original template after IDing the drift.

    Lessons Learned:

    • Create CloudFormation Stack
    • Terminate an EC2 instance for stack drfit
    • Eliminate drift from stack

    Create Key Pair:

    • Before you get into the house, gotta have keys right?!

    Create CloudFormation Stack:

    • I think what AWS has in the “infrastructure composer” is sick, both options of “canvas” and “template” are so slick, also toggling between “YAML” & “JSON” is epic!
    • After the template is created, go ahead & select your VPC as well as subnet of choice
    • Tahhhhh DAhhhhhhhhhhhhhhhhhh!!!!

    Terminate an EC2 instance for stack drift:

    • Annnnnd now its time to run some EVILLL experiments, muuhh-hahahaha… ahemm..
      • Go to your EC2 instances
    • Change instance 3 security groups
    • Delete/Terminate instance 1!!
    • Now edit your security group inbound rules
      • Add HTTP & HTTPs
    • Go to S3
    • Detect drift on CloudFormation stack
    • You can see the details of your drift detection & compare the before/after

    Terminate Drift on Individual Resource:

    • Put the “afterdriftdetection” file in & prepare for re-upload

    Update Stack to Eliminate Drift:

    • Go giggles, you can manually re-add the security group and re-enable the s3 static web hosting… OR just upload the other file & see the magic happen.
      • Cuz as as seen above, AWS tells you the difference for the drift & w/that code you can re-update the file for re-upload. #ohhhyeaaaaah
    • Dont forget to delete your stack if your done, orrrr it will stay there – – – … 4Evahhhh

    Gettin’ cheaper infrastructure w/CloudFormation

    by EarpMoonWater, posted in aws

    Goal:

    GREAT-SCOTT! One just realized our EC2 instance is more compute power than required, & thats not all! Plus were spending wayyy to much chedahhhhhhhh (we want to save for more other goodies – like Pokemon cards & new fancy coffee mugs.. just a thought)

    Lessons Learned:

    • Configure InstanceType Parameter to “t3.micro”
    • Launch Updated stack & ensure EC2 can connect

    The Appetizer before configuring “t3.micro” & Updating the stack:

    Configure InstanceType Parameter to “t3.micro”:

    • After maneuvering to your CloudFormation stack & selecting update – take a peak at the template as seen below.
      • Don’t fret, all these lines can be leveraged from the link above in the github repository.
    • Screenshot below shows the “Default: t3.small” that requires update
    • This is a perty-neat feature I thunk you would find dope. Instead of lines of code, you can mold your own visual CloudFormation by selections on the side.
      • OR you can just see how each AWS service connects to one another.
    • After you make the minor edit for the EC2 size, select validate
    • Once that is complete, your screen will look like this below

    Launch Updated stack & ensure EC2 can connect:

    • Queue Jeopardy theme song…
      • After a couple minutes you will see updates to your template
    • Scroll down to find your instance ID to see if your instance update is complete
    • SEEE!??!
    • Wanna double check? Go to outputs & lastly snag your Public IP address

    Create a Blog w/IaC, maybe?

    by EarpMoonWater, posted in aws

    Inspiration is clutch & I received it for starting this bad boy, so why not dedicate the first post in how I Frankensteined (woah – I created a blog, a blog post, & a past tense verb all in one) it together?

    My Goal:

    Was to create a blog & WordPress site – I then had a brain blast (Queue Jimmy Neutron), what if I did this through some from of IaC? So I tried the basic goodies, you know:

    • Terraform
    • Ansible
    • Docker
    • AWS
    • ChatGPT
      • WUT!?
    • Click-Opps
      • Back-pocked that for last on the learning journey

    All were fun to mess w/& see where I got stuck quicker than others to debug some of the code. However this post follows the option of AWS & I see joy in posting the other journeys I had later, but for now lets not see double & jerk that pistol & go to work (name that movie).

    Lessons Learned:

    • New ways to spend my Bennies ($$$) w/a AWS Account, ayyyy
    • Create an RDS instance for the MySQL database
    • Create an EC2 instance for the WordPress application
    • Install and configure WordPress on EC2
    • Upload and download files to and from S3
    • Access your WordPress site from the internet

    Step 1: Create a RDS instance for MySQL Database

    • Prolly important to have something to store “my precious” (another movie quote) data aka goodiezzzz

    Step 2: Create EC2 Instance

    • I wanted to get virtual & had a plethora of options to configure w/AMI, instance type, storage, tags, key names, security groups, etc.
      • Oh yeah, I overlooked the key pair part…I didn’t save/remember that information – so I had to re-do this. #DOAHHHHH

    Step 3: SSH into EC2

    • Here was a quick double check of my work that helped me re-navigate in the console to find key information to plug-in to my SSH command (yeah, I used PowerShell. Why? Cuz its the most powerfullest, duh)
      • Example Below:
        • ssh -i wordpress-key.pem ec2-user@public-ip-address
    • Then after some yum & systemctl – I had an apache test page… Woah, I know fancy.
    • Really had to pay attention to the next handful of commands to download the latest WordPress Package, Extract it, change ownership w/some chown, & then nano/vi into the configuration file.
    • Couple Example Below (sparing you all the commands):
      • wget https://wordpress.org/latest.tar.gz
      • tar -xzf latest.tar.gz
      • sudo chown -R apache:apache /var/www/html/
        sudo find /var/www/html/ -type d -exec chmod 755 {} \;
        sudo find /var/www/html/ -type f -exec chmod 644 {} \;
      • sudo nano /var/www/html/wp-config.php
    • Then after copy-pasta the public-IP-Address from AWS I started to click more stuff..

    Conclusion:

    • Just like that it was done & could check into the blog & AWS to see the specimen…. ANNNNND then I tore it down. Why? Cuz I was intrigued by the other options available & see the other avenues to create a blog. I don’t have a favorite, but as mentioned above I’ll have posts about how to create a WordPress blog in the handful of options above. Yeah, even some Chat GPT action, stay tuned.