AWS Certified Solution Architect


AWS Certification - Solution Architect


Things to Know
- http://en.wikipedia.org/wiki/List_of_DNS_record_types

 CNAME record - (Canonical Name record) - (http://en.wikipedia.org/wiki/CNAME_record)
is a type of resource record in the Domain Name System(DNS) used to specify that a domain name uses the IP addresses of another domain, the "canonical" domain.

ftp.example.com  ------>
www.example.com  ------>      A record (example.com) -----> IP Address
If you need to change the IP-address you only need to change at one place (A record)

CNAME records must always be pointed to another domain name and never to an IP-address

bar.example.com CNAME foo.example.com
foo.example.com A     192.168.1.1

bar is pointing to a CNAME record of foo.example.com, foo inturn is pointing to IP address 192.168.1.1
foo is the actual Canonical Name (CNAME) of bar, bar is an alias for the Right hand side (RDATA portion) which is
a canonical name.

 DNAME Record - Deligation Name Record

Elastic Load Balancing 

When the beanstalk environment is spined up AWS beanstalk provisions the resources necessary. resource include one load balancer (ELB) an AutoScaling group and one or more EC2 instances
Every environment has a CNAME(URL) that points to a load balancer,

AWS Elastci Beanstalk (Enviornment tier/platform/enviorment type)

Has two enviornment tiers  -- Web server tier or Worker tier
Each enviornment tier determines what resources available for the task

Beanstalk provisions the following resources- ELB, AutoScaling group, one or more EC2 instances
Every environment has a CNAME (URL) that points to the load balancer. This
URL is aliased in Amazon Route 53 to an ELB URL by using the CNAME record.
Route 53 is a higly available and scalable domain name system. The HM - host manager resides in EC2 instance and is responsible for deploying app, event aggregation, monitoring, patching, log rotation etc..

AWS resources created for a worker environment tier include an Auto Scaling group, a minimum of one EC2 instance up to a maximum of four instances, and an IAM role. For the worker environment tier, AWS Elastic Beanstalk also creates and provisions an Amazon SQS queue if you don’t already have one.

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