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cloud engineer

Feedburner HTTPS Feed

When Google acquired Feedburner a few years ago, we thought it would make Feedburner a better product. The opposite has happened. Google has basically shelved the Feedburner product. There hasn’t been any updates to Feedburner the last 5 years.

If you’ve recently updated your site from http to https, you may have noticed that https feeds are not supported. It looks like Google doesn’t plan on updating Feedburner anytime soon. If you want to replace Feedburner, take a look at couple of options. Try FeedBlitz or perhaps even Mailchimp.

In addition, you can import your current subscribers, and never miss a beat.

Use Object Versioning With CloudFront

If you are using AWS CloudFront, you can avoid costly invalidations by using object versioning. Due to the nature of CloudFront, overwriting to the same file will not have any effect until caching is invalidated. The default timeout for CloudFront is 24 hours. If you have a website and you’ve overwritten your logo image, the updated image file will not be reflected on your site due to the caching timeout is 24 hours. To avoid invalidation, enable object versioning by adding a policy when overwriting files.

# Logo Image
<a href="logo.png">Website Logo</a>
#
# Implement object versioning. 
# Increase the filename after each logo change.
#
<a href="logo-001.png">Website Logo</a>
<a href="logo-002.png">Website Logo</a>
<a href="logo-003.png">Website Logo</a>
<a href="logo-004.png">Website Logo</a>

Each time the logo is updated, change the filename to avoid CloudFront invalidation.

AWS Boto3 Client

Boto is the Amazon Web Services (AWS) SDK for Python. It enables Python developers to create, configure, and manage AWS services, such as EC2 and S3. Boto provides an easy to use, object-oriented API, as well as low-level access to AWS services.

Here’s a quick example how to query for AWS resources.

import logging
import boto3
from botocore.exceptions import ClientError
 
# set aws profile
session = boto3.Session(profile_name="default")
 
# get buckets
s3 = session.client('s3')
results = s3.list_buckets()
 
# display buckets
print('Existing buckets:')
for key in results['Buckets']:
    print(f'{key["Name"]}')
 
# get ec2 instances. set region.
ec2 = session.client('ec2', region_name='us-east-1')
results = ec2.describe_instances()
 
# display instances
for key in results["Reservations"]:
      for instance in key["Instances"]:
           instance_id = instance["InstanceId"]
           instance_type = instance["InstanceType"]
           availability_zone = instance["Placement"]["AvailabilityZone"]
           print(instance_id + "\t" + instance_type + "\t" + availability_zone)
 
# get list of users
client = session.client('iam')
results = client.list_users()
 
# display list of users
for key in results['Users']:
    print (key['UserName'])

GCP Web Server

Here’s a quick script to stand up a web server based on Centos image.

gcloud compute instances create [VM-NAME] \
    --zone=[ZONE] \
    --image-family=debian-9 \
    --image-project=debian-cloud \
    --tags=allow-ssh,allow-health-check \
    --subnet=lb-subnet \
    --metadata=startup-script='#! /bin/bash
apt-get update
apt-get install apache2 -y
a2ensite default-ssl
a2enmod ssl
vm_hostname="$(curl -H "Metadata-Flavor:Google" \
http://169.254.169.254/computeMetadata/v1/instance/name)"
echo "Page served from: $vm_hostname" | \
tee /var/www/html/index.html
systemctl restart apache2'

Split A Large File

How to split a large file. 

split -b 500MB httpd.log
ll -lh
total 1.9G
-rw-r--r-- 1 root root 954M Mar 25 12:35 httpd.log
-rw-r--r-- 1 root root 477M Mar 25 12:38 xaa
-rw-r--r-- 1 root root 477M Mar 25 12:38 xab

Split with an output file.

split -b 200M httpd.log split.log
ll -lh
total 1.9G
-rw-r--r-- 1 root root 954M Mar 25 12:35 httpd.log
-rw-r--r-- 1 root root 200M Mar 25 12:52 split.logaa
-rw-r--r-- 1 root root 200M Mar 25 12:52 split.logab
-rw-r--r-- 1 root root 200M Mar 25 12:52 split.logac
-rw-r--r-- 1 root root 200M Mar 25 12:52 split.logad
-rw-r--r-- 1 root root 154M Mar 25 12:52 split.logae