Post on 16-Oct-2020
Stuff I do
Follow me!
https://pasztor.at
@janoszen
About this talk
1. The problem with CDNs
About this talk
1. The problem with CDNs
2. How does a CDN work?
About this talk
1. The problem with CDNs
2. How does a CDN work?
3. Static content CDN
About this talk
1. The problem with CDNs
2. How does a CDN work?
3. Static content CDN
4. Hosting dynamic content
Assumptions
You know what HTTP is.
Assumptions
You know what HTTP is.
You know what a DNS is.
Assumptions
You know what HTTP is.
You know what a DNS is.
You know what a CDN is.
Warning!
Don’t do this at home!This is as experimental as it gets.
The problem with CDNs
Low-traffic sites don’t work well with a CDN
The problem with CDNs
The problem with CDNs
The problem with CDNs
The problem with CDNs
The problem with CDNs
The problem with CDNs
The problem with CDNs
The problem with CDNs
The problem with CDNs
The problem with CDNs
User CDN Origin
GET /avatar.jpg
Cache
The problem with CDNs
User CDN Origin
GET /avatar.jpg
Cache
The problem with CDNs
User CDN Origin
GET /avatar.jpg
Cache
GET /avatar.jpg
The problem with CDNs
User CDN OriginCache
GET /avatar.jpg
GET /avatar.jpg
The problem with CDNs
User CDN Origin
GET /avatar.jpg
Cache
GET /avatar.jpg
The problem with CDNs
User CDN OriginCache
GET /avatar.jpg
The problem with CDNs
User CDN OriginCache
~30-40 ms ~160 ms
The problem with CDNs
User CDN OriginCache
~30-40 ms ~160 ms
~30-40 ms~10 ms
The problem with CDNs
User CDN OriginCache
~30-40 ms ~160 ms
~160 ms
~30-40 ms~10 ms
The problem with CDNs
User CDN OriginCache
~30-40 ms ~160 ms
~160 ms~160 ms
~200 ms
~50 ms~30-40 ms
~10 ms
The problem with CDNs
Workaround:
The problem with CDNs
Workaround:
Cache-Control: s-maxage=31536000
The problem with CDNs
Caveat:
All files must have unique URLs!
Does not always work.
How do CDNs work?
Locating the properedge node
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4
I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4
I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4
I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4
I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4
I have 1.2.3.4!
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4
1.2.3.4
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
1.2.3.4
1.2.3.4
3 hops
6 hops
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA1.2.3.4 1.2.3.4
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA1.2.3.4 1.2.3.410.1.0.1 10.2.0.1
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA1.2.3.4 1.2.3.410.1.0.1 10.2.0.1
What is the IP for pasztor.at?
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA1.2.3.4 1.2.3.410.1.0.1 10.2.0.1
10.1.0.1
How do CDNs work?
User
CDN POP in Europe CDN POP in the USA
Anycast is ONLY used for DNS lookups!
See https://engineering.linkedin.com/network-performance/tcp-over-ip-anycast-pipe-dream-or-reality
Hosting static content
Part 1:Finding a DNS provider
Hosting static content
Anycast servers
Hosting static content
Anycast servers
Latency- or GeoIP based responses
✓
✓
Hosting static content
Anycast servers
Latency- or GeoIP based responses
Hosting static content
eu-central-1.glb.techblog.cloud. IN A 18.194.241.96
us-east-1.glb.techblog.cloud. IN A 54.152.113.29
us-west-1.glb.techblog.cloud. IN A 52.9.244.13
Hosting static content
eu-central-1.glb.techblog.cloud. IN A 18.194.241.96
us-east-1.glb.techblog.cloud. IN A 54.152.113.29
us-west-1.glb.techblog.cloud. IN A 52.9.244.13
glb.techblog.cloud. IN ALIAS eu-central-1.glb.techblog.cloud.
glb.techblog.cloud. IN ALIAS us-east-1.glb.techblog.cloud.
glb.techblog.cloud. IN ALIAS us-west-1.glb.techblog.cloud.
Hosting static content
Hosting static content
Part 2:Docker
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance My laptopEC2 instanceEC2 instance
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
ECS AGENT
My laptop
ECSECSECS
EC2 instance
ECS AGENT
EC2 instance
ECS AGENT
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
ECS AGENT
WEB SERVER
My laptop
ECSECSECS
EC2 instance
ECS AGENT
WEB SERVER
EC2 instance
ECS AGENT
WEB SERVER
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
ECS AGENT
WEB SERVER
My laptop
ECSECSECS
EC2 instance
ECS AGENT
WEB SERVER
EC2 instance
ECS AGENT
WEB SERVER
ECR
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
ECS AGENT
WEB SERVER
My laptop
ECRECSECSECS
EC2 instance
ECS AGENT
WEB SERVER
EC2 instance
ECS AGENT
WEB SERVER
Docker Image
Webserver Content
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
ECS AGENT
WEB SERVER
My laptop
ECRECSECSECS
EC2 instance
ECS AGENT
WEB SERVER
EC2 instance
ECS AGENT
WEB SERVER
Docker Image
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
ECS AGENT
WEB SERVER
My laptop
ECSECSECS
EC2 instance
ECS AGENT
WEB SERVER
EC2 instance
ECS AGENT
WEB SERVER
Docker Image
ECR
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
ECS AGENT
WEB SERVER
My laptop
ECRECSECSECS
EC2 instance
ECS AGENT
WEB SERVER
EC2 instance
ECS AGENT
WEB SERVER
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
WEB SERVER
My laptop
ECR
EC2 instance
WEB SERVER
EC2 instance
WEB SERVER
ECS AGENT
ECSECSECS
ECS AGENT
ECS AGENT
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
WEB SERVER
My laptop
ECSECSECS
EC2 instance
WEB SERVER
EC2 instance
WEB SERVER
ECS AGENT
ECR
ECS AGENT
ECS AGENT
Hosting static content
us-west-1 us-east-1 eu-central-1
EC2 instance
ECS AGENT
WEB SERVER
My laptop
ECRECSECSECS
EC2 instance
ECS AGENT
WEB SERVER
EC2 instance
ECS AGENT
WEB SERVER
Hosting dynamic content
Can it run Wordpress?
Hosting dynamic content
us-west-1 us-east-1 eu-central-1
EC2 instanceEC2 instanceEC2 instance
Hosting dynamic content
us-west-1 us-east-1 eu-central-1
EC2 instanceEC2 instanceEC2 instance
INTERNET
Hosting dynamic content
us-west-1 us-east-1 eu-central-1
EC2 instanceEC2 instanceEC2 instance
INTERNET
Docker Swarm Overlay Network
Hosting dynamic content
us-west-1 us-east-1 eu-central-1
EC2 instanceEC2 instanceEC2 instance
INTERNET
WEB SERVER
WEB SERVER
WEB SERVER
Hosting dynamic content
us-west-1 us-east-1 eu-central-1
EC2 instanceEC2 instanceEC2 instance
INTERNET
WEB SERVER
WEB SERVER
WEB SERVERGALERA GALERA GALERA
Hosting dynamic content
Hosting dynamic content
Unsolved issues:
Hosting dynamic content
Unsolved issues:
Distributing Static Content
Hosting dynamic content
Unsolved issues:
Distributing Static Content
Downtime-less Updates
Hosting dynamic content
Unsolved issues:
Distributing Static Content
Downtime-less Updates
Monitoring
Summary
Is it worth it?
Summary
Summary
Summary
Summary
Summary
Probably not.
Summary
Questions?
Many thanks to
Bence Sántha, Dan Radenković, Gábor Vereb, János Angeli, Krisztián Papp
for their inspiration and feedback.