AWS Platform- Cheet Sheet

My quick cheets on AWS Platform

Tips

  • Stateless Services – RDS, DynamoDB, Elasticache, Lambda
  • Stateful services – ELB
  • High Availability services – DynamoDB, S3, SQS (data automatically replicated in multiple AZ)
  • RDS – customer has the setup high availability – Multi AZ and EC2 by auto scalling
  • for storing seesion data – Elasticache, DynamoDB
  • NGINX can be hosted in – EC2
  • Schema-less DB – DynamoDB
  • Durable and no downtime DB – Aurora
  • To monitor API activity – CloudTrail
  • Enable CloudTrail for all regions. if new region is added in future, cloudtrail will create same trail in the new region.
  • For DR – use route53 to divert the traffic to static website
  • VM Import / Export – to import instances from on prim to aws (windows, Linux VM’s uses VMware ESX or workstations, microsoft Hyper-V and Citrix xen formats)
  • CloudTrail automatcally encrypt the logs by default ussing amazon S3 server side encryption (SSE). you cqn choose to encrypt using KMS
  • CloudSearch –
  • EMR with spot instance nodes – cost effective
  • AWS WAF – Web Application Firewall -protect your app from web vulnerability (XSS)
  • AWS Config
  • Inspector vs WAF vs Trusted advisor
  • Data Pipeline – can move the data from dynamoDB to S3
  • Fault tolerance – Auto Scalling, Multi AZ –
  • High Availability – Auto Scalling, Multi AZ
  • OpsWorks – stack based
  • High Availability – Create NAT Gatway in multiple AZ, load balancer in multi AZ
  • NATGatway cannot send traffic over VPC endpoints, VPN connections, AWS direct connect or VPC peering.
  • VPC endpoints doesnt support cross region S3 requests
  • A Records – Address record – used to translate from a domain name to the IP address. A records are always IPv4. IPv6 is AAA.
  • CName – Canonical Name – used to resolve one domain name to another. You can use mobile.aacloud.com to m.aacloud.com so users can use both and its points to same dns
  • Alias – same as CName. Cant use CNAME for naked domains
  • EBS replicated in multiple AZ by default
  • VPC Peering can be done across the region
  • CloudTrail – API activity, Monitor Route53
  • CloudWatch – Monitor, Alarm, Send Notifications, can detect errors from logs for lambda

Limits

  • EC2
  • 5 elastic ip address
  • uptime SLA for EC2 and EBS – 99.95
  • 20 EC2 instances per region (depends on the family). New accounts may start with lower limit. Can be increased by contacting AWS
  • S3
  • 100 buckets per account – can increase by contacting AWS
  • No limit
  • 1 object – 0 bytes t0 5 TB
  • Single put max size is 5 GB
  • Amazon recommends Multipart upload for more then 100 MB
  • S3 standared – 99.99% Availiabilty, 99.999999999 Durability
  • S3 IA- 99.99% Availiabilty, 99.999999999 Durability
  • S3 onezone IA – 99.5% Availiabilty, 99.999999999 Durability
  • S3 RRS – 99.99% Availiabilty, 99.99 Durability
  • DynamoDB
  • 256 tables per region – can increase by contacting AWS
  • 5 local secondary index – cannot increase secondary index (both local & global)
  • 5 global secondary index (so total is 10)
  • Max limit of item collection is 10 GB
  • Smallest amount of capacity unit can be purchased is 100 (both reads and writes)
  • Max size of item in dynamoDB = 400 kb
  • Number if attributes item can have = no limit, but total size including attribute names and values should not exclude 400 KB
  • Result set from a scan per call is limited to 1 MB, use LastEvaluateKey to reterive more results
  • Capacity unit calculation, unless its mentioned – Strongly consistent
  • can support maximum of 3000 read capacity units and 1000 write capacity units
  • Max length of sort key value – 1024 bytes
  • Max length of sort key value – 2048 bytes
  • SWF
  • Max 100 SWF domains
  • Max 10000 workflow and activity types (in total)
  • SWF workflow can live upto 1 year
  • Maximum open activity tasks – 1000
  • SNS
  • Topic name
    • Should be unique within aws account
    • Limited to 256 characters
    • Alphanumeric, -, _ are allowed
  • Subscription requests are valid for = 3 days for confirmation
  • 100,000 topic per account
  • 10 million subscription per topic – contact aws for more for both
  • SQS
  • No limit
  • 1 million request per month – free tier
  • Then 0.50$ for every million requests
  • Message size, 1 kb to Max 240 KB
  • Retention – 1 min to 14 days
  • Default retention – 4 days
  • Visibility time out 30 seconds to 12 hours
  • Long poling max – 0 to 20 seconds
  • CloudFormation
  • Templates – No limit
  • Stacks per account – 200 – can increase by contacting AWS
  • 60 parameters and 60 outputs in a template
  • ELB
  • No cost
  • 200 subnets per vpc – call aws for more
  • Route53
  • Default limit is 50 domain names. but can be increased by contacting AWS
  • Lambda
  • Lamda default timeout – 3 seconds
  • Max execution duration per request – 300 seconds (5 mins)
  • You can set memory in 64 MB increments from 128 MB to 3 GB
  • Minimum 128 MB and Max is 3008 MB (64 MB increments)
  • ephemeral disk capacity (/tmp space ) = 512 MB

Acronym

  • IOPS – Input Output per Second
  • SSD – Slot State Drive
  • AMI – Amazon Machine Instance
  • HVM – Hardware Virtual Machine (X – Para virtualization)
  • NFSv4 – Network File System V4
  • OTLP – Online Transaction Processing
  • OLAP – Online Analytics Processing
  • SAML – Security Assertion Markup language
  • CORS – Cross Origin Resource Sharing
  • RTMP – Real Time Messaging Protocol
  • HSM – Hardware Security Module ??
  • API – application programming interface
  • rps – requests per second
  • DAX – Dynamo DB Accelerator
  • NACL – Network Access control List
  • CIDR – Classless Inter-Domain Routing
  • NAT – Network Address Translation


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