EC2 for SysOps

21. [SAA] EC2 Hibernate Overview

In this lecture we are going to talk about a new feature from EC Two called EC to Hibernate. So let's get started. We know we can stop and terminate our two instances. And what happens? Well, when we stop them, the data on disk, if it's an EBS volume, is kept intact for the next time. And if we terminate our instance, then any data on ourEBS volumes that is root that is also set up to be destroyed alongside our instances is going to be lost. OK, but if it's an EBS volume that is attached as a secondary drive and that it's not meant to be destroyed when your instance is being terminated, then you will keep that data, obviously. So these are behaviours we know and we've seen before. And when we start an instance, what happens? Well, at first start, the operating system is going to boot and then it's going to play the script from the EC Two user data. This is how we customise our instances a little bit. And if we stop it and then restart it, the operating system will boot and your application will start. Obviously, if you set it up, your application will start. And if you have an internal cache on your instance, then the cache will be warmed up. And all these things can take a bit of time if your application is slow to start or if your cache is slow to get warmed up. So there's a new option called EC to Hibernate. What happens when we use EC to hibernate? All the data in memory or state is preserved. So that means that all the data in your RAM is going to be preserved, so that's your memory. So that means that when you restart your instance after hibernating it, the instant boot is going to be much faster because, in fact, the operating system has not been stopped or restarted. As we'll see in the hands-on,the operating system will still be up. So it's like we just froze or hibernated our issue to an instant state and we can restart it to get back into a state much faster. What happens in the hood? because it's really tough to maintain an inmemory state, obviously. Well, the whole state of the RAM is going to be dumped into a file onto the root EBS volume. And that the root EBS volume therefore must be encrypted. And so what happens is this. So we have our EC Two instance that is running and there's an encrypted Amazon EBS root volume and the RAM upon we stop and hibernate. What's going to happen is that the RAM is going to be dumped onto the encrypted Amazon EBS rootvolume and then the instance will be stopped. So there will be a shutdown instance, but not the OS. And then when we restart it, the RAM will go from the EBS volume into the RAM instance and the instance will be running. So why would we do this? Well, the use cases are that if you want to keep a running process running, or if you want to save the RAM state, or if you have services that take a lot of time to initialise and you don't want to really initialise them on start, then you would hibernate your instance and restart it, and then your instance would be kept. Okay, so it's good to know about EC Two hibernate. It doesn't support all the EC two instances currently supported by Cfour, C five, C three, M four, and all the ones in this place right now. You can see CM and R. Obviously, this can change over time as the feature gets better. The RAM size must be less than 150GB. That's the current limitation because you have to spend and put all of that RAM into disc so you have a big enough root EBS volume. It's currently not supported for bare metal instances. The AMI that it supports currently is AmazonLinux Two, or Linux One, or Ubuntu. You can use the root volume. So it has to be an EBS volume. It cannot be an instance store. It has to be encrypted and it has to be large enough to support the dump of the full RAM size. Finally, it's only available for on-demand and reserved instances, so not spot instances. And there is a current limitation that the instance cannot be hibernated for more than 60 days. So this right here probably is not what the exam will test you on. The exam will probably test you on more of the feature itself to save ramp states and hibernate your instance. But this is more of some real world experience that I'm giving you, so if you want to use a feature, you know the limitations. Now, these limitations, like anything inAWS, change really, really quickly. And so it's very, very possible that in the future, obviously, there will be improvements to these things and that maybe more instances will be supported and so on. Okay? So see this as a guideline and a little bit less as a source of truth. Okay? So that's it for this lecture. I'll see you in the next lecture for the practical.

22. [SAA] EC2 Hibernate Hands On

So let's practise using the EC Twohibernation features, so let's launch an instance. We'll choose Amazon X Two. We'll select it. We'll use a T two micro to remain within the free tier Then when you scroll down under shutdownbehavior there is stop Hibernate behaviour and we can enable hibernation as an additional stop behaviour and there's a warning message saying that when we enable hibernation there is space allocated on the root volume to store the instance memory Ram. So we need to make sure that the root volume is large enough to store the RAM contents; the RAM on an ECTwot two micro is 1 GB, so we need to make sure that our root volume is large enough to fit the 1 GB of RAM, so we'll just enable hibernation. Here's a message saying hello. We also need to encrypt the root volume, so 8GB is going to be enough in terms of size, and let's encrypt the root volume with the default key AWS EBS okay.Tags Configuration Security Group Let's bring lunch. Reserve one review and launch one, and we're good to go. So our instance is now created and we have enabled hibernation as a specific staff behavior. How do we prove that hibernation works? So let's connect to our instance using the EC2 instanceconnect and I'm going to connect right now. I will go back into my instance and here we go. We are connected to our instance using east instance So if you do uptime, it says it's been up for zero minutes right now, so we just need to wait a little bit for it to become one minute, but the idea is that uptime tells you how long the instance has been on since its last restart. So as we can see now, we have uptime and we are getting 1 minute of uptime, which means that the instance has been up for 1 minute. OK, great. So let's disconnect from our instance and what we're going to do now is hibernate the instance. To do so, we do instance state and then hibernate the instance. This is going to make sure that all the data on the RAM is stored on our EBS volume. We are hibernating the instance, so we need to wait for it to be stopped. So our instance is now stopped and I'm going to start it again. Now if we do a little mental exercise, if we did not have hibernation and then we stopped the instance and then we started again, we expect the uptime command to return for zero minutes and then one minute because we have effectively stopped and started the instance, but we have hibernated the instance and then started it. And so if that's the case, then we should be able to have the uptime start not at zero, but maybe three or four minutes. So let's connect to the instance and do uptime. And yes, we got up for two minutes because that was really quick. So the idea is that even though we have stopped, quote, unquote, stopped the instance by hibernating it and restarting it from an operating system perspective, the instance was never stopped, it was hibernated. And therefore, the uptime command gives you two or three minutes because it has never, quote,unquote, been stopped from an operating system perspective,which is the whole idea behind hibernation. So that's it. I think it's a really cool demo, and to finish it off, just take your instance and terminate it. That's it. I will see you in the next lecture.

23. EC2 Cleanup

And when you're done with this section, please make sure to delete your EC two instances. Terminate it. Even though this is within the three tiers, it is best practise to keep everything shut down. So that's it for this lecture. I hope you liked it and I will see you at the next lecture.

AMI - Amazon Machine Image

1. [CCP/SAA/DVA] AMI Overview

Now let's talk about what powers are easy to instance, which is an AMA. AMI stands for Amazon Machine Image, and it represents a customised version of a simple to instance. So you can use AI to create it byAWS or you can customise it to make it your own. And what is in the AMI is that we have our own software configuration, we can define and set up the operating system, we can set up any monitoring tool, and if we create our own AMI, we're going to get a faster boot time and configuration time because all the software that we want to install on our EC2 instance is going to be prepackaged through the AMI. So we have to build our own Amis, and they can be built for a specific region, and then they can be copied across regions if we want to use and leverage the AWS global infrastructure, so we can launch these two instances from different kinds of Amis. What we've been doing so far in this course is using a public AMI, and these are provided by AWS. As a result, the Amazon Linux Two AMI is a very popular AMI for AWS, and it was provided by AWS. But we can create our own AMI and, therefore, you have to make and maintain them yourself. There are tools, obviously, to automate this, but this is a task that you have to do as a cloud user. Or finally, you can launch an easy instance from an AWS marketplace AMI, which is an AMI that has been made by someone else and potentially sold by someone else. It is quite common for vendors on AWS to create their own Amis with their own software with a nice configuration and so on, and then they will sell it through the marketplace AMI for you to buy it and to save time, and even you as a user could create a business by selling Amis on the AWS marketplace. This is something that some businesses do. Okay, so the AMI process from anECQ instance, how does it work? Well, we'll start an ECQ instance and we'll customise it. Then we will stop the instance to make sure the data integrity is correct. Then we can build an AMI from it. So this will also create EBS snapshots behind the scenes and then we can finally launch instances from other AMIs. So this is what we'll be doing in the demo in the next lecture. So we have USD one A and we can create the same instance as USD one B. So the process is we launch the instance in USDA one A, we're going to customise it, and then we're going to create an AMI from it. This will be our custom AMI and then in US Eastone B we will be able to launch from the AMI, which will effectively create a copy of our easy to instance. I hope you're excited, and I will see you in the next lecture.

2. [CCP/SAA/DVA] AMI Hands On

So let's practise creating an MI. And before we can create an Mi, we must first create an easy two instance. So let's launch an instance. We'll use Amazon Linux Two. We'll select this, we'll use a two-micro, and then I'll scroll down. We need to specify the user data and then I'm going to copy the code here, but everything but the last line, so do not copy the last line. The reason is that we are going to create an AMI in which we install HTTPD. So we have an Apache web server but we don't want to customise the HTML file yet because it's something we'll do at runtime from the Mi when we actually boot from the Mi. So let's copy everything but the last line into the user data. Click on Add Storage. So now we understand all the options for the EBS volumes, including the delete on termination attributes. We click on Add tags and then click on Configure security group. We can link an existing security group to the Launch Wizard One security group. We'll review the Launch and Launch and we'll use the existing key pair EC Two tutorial. So we're good to go. Now that our instance has been launched, I clicked View instances, and we have this new instance in the pending site for creation. So let's give it some time to bootup and I'll get back to you. So the instance is running and if I copy the public IP and paste it in the browser, as you can see, it goes too quickly and it says this site cannot be reached. It's a good way to show the errors. But as you can see, because the EC2 instance has not bootstrapped yet, not everything is installed yet on the E2 instance, we're getting a connection error. But if I refresh this page, for example, and wait a little bit, at some point the EC 20 script will be executed and the HTTP web server will be created. So it's always good to demonstrate that everything is immediate, and this is also one of the reasons we create an Mi. So all this bootstrap time, which is going to be 20-30 seconds for this easy instance,will be gone once we create an AMI. So here's the test page. So, because we have not customised the HTTP webpage, we get this standard page and you say you need to now customise your website. But anyway, this is great. So that means that everything is installed in our instance and we're good to go. So now what we have to do is to create an AMI from this instance. So to do so, you can right click and then we're going to do images and templates and create an image. And so, from this image, we can say this is our demo image. We're going to create an AMI from our instance. So we are good to go. We're going to do a snapshot of our root EBS volume and then I will click on Create image. So now this has been created. Okay, And now what I can do is that I can launch an easy instance from this. Am I? So let's click on Launch Instances. We can click on My Amis, and we need to probably wait a little bit of time for this. Am I to be created? So, as we see from the left hand side, if we click on AMI's, the status of this AMI is in a pending state. So we need to wait for it to be ready before we can launch an instance from it. Myami is now available and I can go to instances launch instance. I can go on the left hand side into my Amis and see that yes, my demo image was being created. I can select it using micro-configuration of the instancedetails and here I'm going to customise just a little bit this instance using some new data. So what I will do is that I will copy the very first line because it is very important. So copy the first line, then make sure you're on the new line, and then copy the very last line. So what this will do is that it will only run one command when the easy user boots up, which is to create this index of HTML file to customise the message when our instance starts. And so, as you can see now, we don't have to reinstall HTTPD and so on because it is already installed as part of the AMI. Now that it's in storage, add tags. Let's just say the name of this image is from the AMI configured security group. We're going to use our Launch Wizard One security group review and launch yes, I want this key pair. And now view our instances. And as we can see now, we have three instances. One is terminated, one running, and one pending. So this is the whole power of the cloud, really. And so these two EC instances are spent right now. Let's open the IPC four addresses. Let's wait for it to be in a running state. So let's wait for the instance to start and now it is in running states. The test page has already appeared, as you can see. So that means, because the Apache HTTP server was already installed, it disappeared right away. And if I refresh, I just need to wait for the easy two user data to execute. Here we go. And now we get the hello world from the private IP of the instance. So this really shows the power of AMI. We went much quicker into our boottime because the software we needed was already installed on our EC Two instance. so a lot quicker. So you can imagine how I can be useful for packing up your usual software or your security software, firewalls, custom configurations, or stuff like this. So that's it for this lecture. I hope you liked it. Before you finish this lecture, we don't need these. So you can take these instances and terminate them, and we're good to go. So that's it. I will see you in the next lecture.

ExamSnap's Amazon AWS Certified SysOps Administrator - Associate Practice Test Questions and Exam Dumps, study guide, and video training course are complicated in premium bundle. The Exam Updated are monitored by Industry Leading IT Trainers with over 15 years of experience, Amazon AWS Certified SysOps Administrator - Associate Exam Dumps and Practice Test Questions cover all the Exam Objectives to make sure you pass your exam easily.