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krishnamurthydasari / AWS Transit Gateway Route Propagation
Last active April 19, 2024 08:09
AWS Transit Gateway Route Propagation
How route propogation happens at Transit gateway route table:
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This applies when you have VPN and also Direct connect both uses transit gateway as aws side of gateway. then these routes are followed.
Ref: Refer to "Route evaluation order" section at https://docs.aws.amazon.com/vpc/latest/tgw/how-transit-gateways-work.html
Ref: https://www.linkedin.com/pulse/aws-transit-gateway-tgw-explained-ahmed-ali/
Transit gateway routes are evaluated in the following order:
Network Architecture Models
Blueprint or set of instructions to communicate systems each other
Each layer has specific purpose or a job
Each layer uses specific protocols and standards
OSI Layers and Purpose:**************
========================
Layer 7 - Application Layer - Provides and interface between communication software and applications that need to communicate
Layer 6 - Presentation Layer - Defines and negotiates data formats such as ASCII, Binary, JPEG. Encryption also a presentation service
Layer 5 - Sessions Layer - Defines how to start, end and control sessions.
Domain 1: Incident response
Domain 2: Logging and Monitoring
Domain 3: Infrastructure Security
Domain 4: Identity and Access Management
Domain 5: Data Protection
Domain 1: Incident response:
============================
*****Notes by trainer: https://docs.google.com/document/d/11_1lNSNMI7tRTmfBR74FOkaQbDfVZPZ7u0H4tFXRrGs/edit?usp=sharing
@krishnamurthydasari
krishnamurthydasari / Kubernetes Introduction
Last active February 16, 2024 12:54
Kubernetes Introduction
What are containers?
Containers are completely isolated environments, as in they can have their own processes or services, their own network interfaces, their own mounts, just like Virtual machines, except that they all share the same OS kernel.
What is Orchestrator?
Orchestrator is a platform which enables to control connectivity between containers and automatically scale up or down based on the load. This whole process of automatically deploying and managing containers is known as Container Orchestration.
What is Node?
@krishnamurthydasari
krishnamurthydasari / AWS EKS Notes
Last active February 1, 2021 11:37
AWS EKS Notes
Basics:
=======
http://kubernetesbyexample.com/
- A replication controller (RC) is a supervisor for long-running pods. An RC will launch a specified number of pods called replicas and makes sure that they keep running, for example when a node fails or something inside of a pod, that is, in one of its containers goes wrong.
example:
kubectl apply -f https://raw.githubusercontent.com/openshift-evangelists/kbe/master/specs/rcs/rc.yaml
@krishnamurthydasari
krishnamurthydasari / Direct connect Notes
Last active March 27, 2019 21:50
Direct connect Notes
Creation of Dx connection
You need Location details
Port speed
Creation of VIF:
You dont need to create VPCs before, or no dependancy with this. You can manage with creating DxGW and later point in time you can create VGW and associate with DxGW
ASN - This is going to be customer ASN
- AWS side ASN will be available when you download router configuration
@krishnamurthydasari
krishnamurthydasari / Deploying application in 2 different VPCs Vs Deploying in two AZs in single VPC
Last active June 15, 2018 15:13
Deploying application in 2 different VPCs Vs Deploying in two AZs in single VPC
It is always recommended we deploy application across multiple AZs within same VPC instead of deploying in multiple VPCs itself. Below are 2 important points,
1) When you deploy application in two AZs(1a and 1b) in same VPC, AWS will make sure those AZs (1a and 2b) are deployed in 2 separate data centers.
2) When you deploy application in two VPCs
VPC1 --> AZ 1a
VPC2 --> AZ 1b
There is no guarantee that 1a from VPC1 and 1b from VPC2 are deployed in separate data centers. It is completely automated process from AWS to pick data center when you select AZ. So possible that both 1a and 1b are deployed on to same physical data center.
For example, AWS has three AZs in Ireland region (i.e. 3 data centers). so 1a, 1b and 1c not always mapped to fixed data center. For one customer (or VPC) 1a can be data center1 and for other customer it may be 1b for the same data center.
@krishnamurthydasari
krishnamurthydasari / Cloud Governance and Security
Last active June 6, 2018 20:14
Cloud Governance and Security
Governance - Oversight role and process by which companies manage and mitigate business risks
Compliance - Process and internal controls to meet the requirements imposed by governance body
Governance
Define
Discover
Monitor
Respond
https://openvpn.net/index.php/access-server/docs/quick-start-guide.html#asclient
download package and install
wget http://swupdate.openvpn.org/as/openvpn-as-2.0.21-CentOS6.x86_64.rpm
If you get any errors as below,
Generating init scripts...
Generating init scripts auto command...
Error: Could not generate server script auto.
@krishnamurthydasari
krishnamurthydasari / ECS Notes
Created March 21, 2018 10:02
Amazon ECS Notes
Amazon Elastic Container Servie: Native Doctor Support on AWS
User Cases:
Configuration and deployment
Microservices
Breaking application into smaller chunks of code
Batch Processing
Building block service
Manage cluster state