Explain what happens with React's "virtual DOM" whenever render fires, and why it's so great.
Whenever React renders the component tree, it looks for changes from the virtual DOM to the actual DOM. If there are c…
13:11Whenever React renders the component tree, it looks for changes from the virtual DOM to the actual DOM. If there are c…
Vikas 13:11In order to ensure events have consistent properties across different browsers, React wraps the browser's native e…
Vikas 13:10this.state._____ inside JSX {} inside render if this.state = { name: "Nick" }; then... {this.state.name}
Vikas 13:10constructor() { super(); this.state = { name: "Vikas" }; }
Vikas 13:09We can use refs to assign form values to properties on the component object. input: dom element passed in the functio…
Vikas 13:08We update state by calling this.setState(), this causes our component to re-render. this.setState({showComments:true…
Vikas 13:08State handles data changes. State is a JavaScript object that lives inside each component. We can access it via this.s…
Vikas 13:08Because they're a constructor. It is not a rendered DOM element YET, it just has the capacity to render out a DOM …
Vikas 13:07A virtual DOM object can update much faster than a regular DOM object. A virtual DOM object can't directly affe…
Vikas 13:06When Component rendering for the second time Virtual DOM checks what element get changed and print the changed element…
Vikas 13:05When you render a JSX element, every single virtual DOM object gets updated.This sounds incredibly inefficient, but th…
Vikas 13:05In React, for every DOM object, there is a corresponding "virtual DOM object." A virtual DOM object is a rep…
Vikas 13:04When we use our defined components, we can add attributes called props. These attributes are available in our componen…
Vikas 13:03In JSX, you can't use the word class. You have to use className instead because JSX gets translated into JavaScrip…
Vikas 13:03It must have exactly one outermost element. var paragraphs = ( <div id="i-am-the-outermost-element">…
Vikas 13:00You should wrap the multi-line JSX expression in parentheses. This looks strange at first, but you get used to it: (…
Vikas 12:59Yes! You can nest JSX elements just like you can do with HTML elements.
Vikas 12:59JSX is not valid JavaScript. Web browsers can't read it! If a JavaScript file contains JSX code, then that file wi…
Vikas 12:58ReactDOM.render(<h1>Hello world</h1>, document.getElementById('app'));
Vikas 12:57JSX is a syntax extension for JavaScript. Basically HTML that goes into a js file to be compiled into real HTML. A JSX…
Vikas 12:55React and JSX Transformer <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/lib…
Vikas 12:53Following are the advantages/benefits and limitations of React Advantages/benefits: ReactJS can be used on client a…
Vikas 12:51React.js is a JavaScript library developed by engineers at Facebook for building user interfaces. ReactJS allows us to…
Vikas 12:48Improves perception of changes between statistical data graphics Helps tell the story of data changes through time …
Vikas 05:49Dundas BI is a completely separate product with a different codebase and an expanded scope, focusing on self-serve bus…
Vikas 05:37Following are the Key Features and Benefits of Dundas BI Self-Serve Business Intelligence: Dundas BI gives you the …
Vikas 05:34Dundas BI is a state-of-the-art business intelligence platform for building and using interactive dashboards, reports…
Vikas 05:30Power BI Desktop is a free desktop application you can install right on your own computer. Power BI Desktop works cohe…
Vikas 19:03Power BI provides all sorts of features to help you get started exploring data in a whole new way. Power BI Pro provid…
Vikas 19:02Here we come with most growing technology related interview questions, the technology is known as Amazon Virtual Priva…
Vikas 18:30Puppet is a Configuration Management tool that is used for deploying, configuring and managing servers. It performs th…
Vikas 23:24Scrum is a simple framework for effective team collaboration on complex projects. Scrum provides a small set of rules …
Vikas 23:23Tools or frameworks that allow source code to be automatically compiled into releasable binaries. Usually includes cod…
Vikas 23:22LXC - (LinuX Container) is an operating system-level virtualization method that allows multiple isolated Linux systems…
Vikas 23:22A structured problem‐solving approach that uses a lean tool called the A3 Problem‐Solving Report. The term "A3&qu…
Vikas 23:22Git is a free, open source distributed version control system tool designed to handle everything from small to very la…
Vikas 23:21Provisioning is the process of preparing new systems for users (in a Continuous Delivery scenario, typically developme…
Vikas 23:20It is a go-live strategy in which code implementing new features is released to a subset of the production environment…
Vikas 23:20NGINX is open source software for web serving, reverse proxying, caching, load balancing, media streaming, and more. .…
Vikas 23:20Acceptance Testing is typically high-level testing of the entire system carried out to determine whether the overall q…
Vikas 23:19Chef is an automation tool that provides a way to define infrastructure as code. Infrastructure as code (IAC) simply m…
Vikas 23:18You can deploy code to production without releasing Release is to make functionality available to end users
Vikas 22:41Collaboration Breakdown the barriers Work as one team end to end Treat Infrastructure as code Support business …
Vikas 00:521. Lack of resources (Developers) 2. Developer are so costly due to lack of resources 3. Difficult to hire good DevO…
Vikas 00:42Elastic Block Store aka EBS is a type of block storage system that provides persistent block storage volumes for use w…
Vikas 00:25It is a software distribution model where applications are hosted by a vendor and made available to customers over the…
Vikas 00:24By using automated testing, continuous integration, continuous delivery and automated infrastructure.
Vikas 00:22It is a software development methods in which requirements and solutions evolve through collaboration between self-org…
Vikas 00:19Below are the steps of build a custome VPC: 1. Create a VPC 2. Create subnets 3. Create an internet gateway (IGW) …
Vikas 00:03AWS CodeCommit: AWS CodeCommit is a fully-managed source control service that makes it easy for companies to host …
Vikas 23:45Ans: This diagram is showing DevOps as the intersection of development (software engineering), technology oper…
Vikas 22:321. Culture. 2. Organization (style including roles). 3. Processes. 4. Tools.
Vikas 22:31AWS DevOps Interview Question: What are the Advantage/Benefits of using AWS for DevOps? Why use AWS for DevOps? Ans:…
Vikas 21:41Speed: Move at high velocity so you can innovate for customers faster, adapt to changing markets better, and grow…
Vikas 21:28DevOps is the combination of cultural philosophies, practices, and tools that increases an organization’s ability to d…
Vikas 21:14Here we come with most growing technology related interview questions, the technology is known as Amazon Virtual Priva…
Vikas 23:41Yes. There are multiple options for your resources within a VPC to communicate with Amazon S3. You can use VPC Endpoin…
Vikas 22:10You will need to disable NAT-T on your device. If you don’t plan on using NAT-T and it is not disabled on your device,…
Vikas 22:09When you launch an Amazon EC2 instance within a VPC, you may optionally specify the primary private IP address for the…
Vikas 22:08The minimum size of a subnet is a /28 (or 14 IP addresses.) for IPv4. Subnets cannot be larger than the VPC in which t…
Vikas 22:08Currently you can create 200 subnets per VPC. If you would like to create more, please submit a case at the support ce…
Vikas 22:07No. To change the size of a VPC you must terminate your existing VPC and create a new one.
Vikas 22:07VPN connection-hours are billed for any time your VPN connections are in the "available" state. You can dete…
Vikas 22:07Yes. You can assign one or more secondary private IP addresses to an Elastic Network Interface or an EC2 instance in A…
Vikas 22:06You can assign any IP address to your instance as long as it is: Part of the associated subnet's IP address ran…
Vikas 22:05Default VPCs are assigned a CIDR range of 172.31.0.0/16. Default subnets within a default VPC are assigned /20 netbloc…
Vikas 22:04You assign a single Classless Internet Domain Routing (CIDR) IP address block when you create a VPC. Subnets within a …
Vikas 22:04You will use the public IP address of your NAT device.
Vikas 22:03Yes, you will need to enable NAT-T and open UDP port 4500 on your NAT device.
Vikas 22:03Amazon does not enforce any restrictions on VPN throughput. However, other factors, such as the cryptographic capabili…
Vikas 22:02Establishing a hardware VPN connection between your existing network and Amazon VPC allows you to interact with Amazon…
Vikas 22:01The DescribeVPNConnection API displays the status of the VPN connection, including the state ("up"/"dow…
Vikas 22:00ClassicLink does not change the access control defined for an EC2-Classic instance through its existing Security Group…
Vikas 22:00Traffic from an EC2-Classic instance can only be routed to private IP addresses within the VPC. They will not be route…
Vikas 21:59ClassicLink cannot be enabled for a VPC that has a Classless Inter-Domain Routing (CIDR) that is within the 10.0.0.0/8…
Vikas 21:59There are two types of VPN connections that you can create: statically-routed VPN connections and dynamically-routed V…
Vikas 21:58IPsec is a protocol suite for securing Internet Protocol (IP) communications by authenticating and encrypting each IP …
Vikas 21:56A hardware VPN connection connects your VPC to your datacenter. Amazon supports Internet Protocol security (IPsec) VPN…
Vikas 21:55Instances without public IP addresses can access the Internet in one of two ways: Instances without public IP address…
Vikas 21:54You can use public IP addresses, including Elastic IP addresses (EIPs), to give instances in the VPC the ability to bo…
Vikas 21:53An Amazon VPC router enables Amazon EC2 instances within subnets to communicate with Amazon EC2 instances in other sub…
Vikas 21:53You can have: Five Amazon VPCs per AWS account per region Two hundred subnets per Amazon VPC Five Amazon VPC Elas…
Vikas 21:51Yes. You can use the AWS Management Console to manage Amazon VPC objects such as VPCs, subnets, route tables, Internet…
Vikas 21:50Yes. You may create a default route for each subnet. The default route can direct traffic to egress the VPC via the In…
Vikas 21:42Yes. You can create route rules to specify which subnets are routed to the Internet gateway, the virtual private gatew…
Vikas 21:41The ClassicLink connection will not persist through stop/start cycles of the EC2-Classic instance. The EC2-Classic ins…
Vikas 21:41The EC2-Classic instance does not become a member of the VPC. It becomes a member of the VPC Security Group that was a…
Vikas 21:41In order to use ClassicLink, you first need to enable at least one VPC in your account for ClassicLink. Then you assoc…
Vikas 21:40Amazon Virtual Private Cloud (VPC) ClassicLink allows EC2 instances in the EC2-Classic platform to communicate with in…
Vikas 21:38Bandwidth between instances in peered VPCs is no different than bandwidth between instances in the same VPC. Note: A p…
Vikas 21:38No. Traffic between instances in peered VPCs remains private and isolated – similar to how traffic between two instanc…
Vikas 21:37No. VPC peering connections do not require an Internet Gateway.
Vikas 21:36No. Peered VPCs must have non-overlapping IP ranges.
Vikas 21:36No. “Edge to Edge routing” isn’t supported in Amazon VPC. Refer to the VPC Peering Guide for additional information.
Vikas 21:34No. You can attach and detach secondary interfaces (eth1-ethn) on an EC2 instance, but you can’t detach the eth0 inter…
Vikas 21:34Yes, however, this is not a use case best suited for multiple interfaces. Instead, assign additional private IP addres…
Vikas 21:34Network interfaces can only be attached to instances in the same VPC as the interface.
Vikas 21:33Network interfaces can only be attached to instances residing in the same Availability Zone.
Vikas 21:33The total number of network interfaces that can be attached to an EC2 instance depends on the instance type. See the E…
Vikas 21:33Yes, assuming the owner of the other VPC accepts your peering connection request.
Vikas 21:32No. Peering connections are only available between VPCs in the same region.
Vikas 21:32AWS uses the existing infrastructure of a VPC to create a VPC peering connection; it is neither a gateway nor a VPN co…
Vikas 21:29If your AWS account has a default VPC, any IAM accounts associated with your AWS account use the same default VPC as y…
Vikas 21:28Yes, however, we can only enable an existing account for a default VPC if you have no EC2-Classic resources for that a…
Vikas 21:28The simplest way to get a default VPC is to create a new account in a region that is enabled for default VPCs, or use …
Vikas 21:27No. Transitive peering relationships are not supported.
Vikas 21:27No. Either side of the peering connection can terminate the peering connection at any time. Terminating a peering conn…
Vikas 21:27Yes, but once deleted, it’s gone. Your future instance launches will be placed in your remaining default subnet(s).…
Vikas 21:26Yes. Contact AWS Support if you've deleted your default VPC and want to have it reset.
Vikas 21:26No. Default VPCs are attached to the Internet and all instances launched in default subnets in the default VPC automat…
Vikas 21:25Yes. You can reserve an instance in Amazon VPC when you purchase Reserved Instances. When computing your bill, AWS doe…
Vikas 21:24Yes, however, an instance launched in a VPC using an Amazon EBS-backed AMI maintains the same IP address when stopped …
Vikas 21:24Yes, you may use Amazon EBS snapshots if they are located in the same region as your VPC. More details are available i…
Vikas 21:23See Differences between EC2-Classic and EC2-VPC in the EC2 User Guide.
Vikas 21:23No. You can use the AWS Management Console, AWS EC2 CLI, or the Amazon EC2 API to launch and manage EC2 instances and …
Vikas 21:20Yes. To launch into nondefault subnets, you can target your launches using the console or the --subnet option from the…
Vikas 21:19Yes. To launch an instance into nondefault VPCs you must specify a subnet-ID during instance launch.
Vikas 21:19The Amazon EC2 console indicates which platforms you can launch instances in for the selected region, and whether you …
Vikas 21:17If your AWS account was created after March 18, 2013 your account may be able to launch resources in a default VPC. Se…
Vikas 21:15When you launch resources in a default VPC, you can benefit from the advanced networking functionalities of Amazon VPC…
Vikas 21:14A default VPC is a logically isolated virtual network in the AWS cloud that is automatically created for your AWS acco…
Vikas 21:13Yes. Cluster instances are supported in Amazon VPC, however, not all instance types are available in all regions and A…
Vikas 21:13One default subnet is created for each Availability Zone in your default VPC.
Vikas 21:12The default VPC CIDR is 172.31.0.0/16. Default subnets use /20 CIDRs within the default VPC CIDR.
Vikas 21:12You can have one default VPC in each AWS region where your Supported Platforms attribute is set to "EC2-VPC"…
Vikas 21:11You can run any number of Amazon EC2 instances within a VPC, so long as your VPC is appropriately sized to have an IP …
Vikas 21:09Yes. DescribeVolumes() will return all your EBS volumes.
Vikas 21:08Yes. DescribeInstances() will return all running Amazon EC2 instances. You can differentiate EC2-Classic instances fro…
Vikas 21:08When you create a subnet you must specify the Availability Zone in which to place the subnet. When using the VPC Wizar…
Vikas 21:07Security groups in a VPC specify which traffic is allowed to or from an Amazon EC2 instance. Network ACLs operate at t…
Vikas 21:06Amazon EC2 security groups can be used to help secure instances within an Amazon VPC. Security groups in a VPC enable …
Vikas 21:06No. An Internet gateway is horizontally-scaled, redundant, and highly available. It imposes no bandwidth constraints.…
Vikas 21:05When you launch an Amazon EC2 instance you must specify the subnet in which to launch the instance. The instance will …
Vikas 21:05You can use AMIs in Amazon VPC that are registered within the same region as your VPC. For example, you can use AMIs r…
Vikas 21:03Amazon VPC is currently available in multiple Availability Zones in all Amazon EC2 regions.
Vikas 21:02Yes. You can use the Amazon VPC Flow Logs feature to monitor the network traffic in your VPC. Amazon VPC & EC2
Vikas 21:00Ping (ICMP Echo Request and Echo Reply) requests to the router in your VPC is not supported. Ping between Amazon EC2 i…
Vikas 20:59Yes. If an Internet gateway has been configured, Amazon VPC traffic bound for Amazon EC2 instances not within a VPC tr…
Vikas 20:59Stateful filtering tracks the origin of a request and can automatically allow the reply to the request to be returned …
Vikas 20:57Amazon VPC enables you to build a virtual network in the AWS cloud - no VPNs, hardware, or physical datacenters requir…
Vikas 20:56Amazon VPC comprises a variety of objects that will be familiar to customers with existing networks: A Virtual Priv…
Vikas 20:55