Track Title: Overview of Windows Azure Virtual Machines (IaaS) Module: Cloud Services and Virtual Machine Availability.

Transcription

1 Track Title: Overview of Windows Azure Virtual Machines (IaaS) Module: Cloud Services and Virtual Machine Availability Module Manual Published: 28 th September 2012

2 Information in this document, including URLs and other Internet Web site references, are subject to change without notice. Unless otherwise noted, the example companies, organizations, products, domain names, addresses, logos, people, places, and events depicted herein are fictitious, and no association with any real company, organization, product, domain name, address, logo, person, place or event is intended or should be inferred. Complying with all applicable copyright laws is the responsibility of the user. Without limiting the rights under copyright, no part of this document may be reproduced, stored in or introduced into a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise), or for any purpose, without the express written permission of Microsoft Corporation. Microsoft may have patents, patent applications, trademarks, copyrights, or other intellectual property rights covering subject matter in this document. Except as expressly provided in any written license agreement from Microsoft, the furnishing of this document does not give you any license to these patents, trademarks, copyrights, or other intellectual property Microsoft Corporation. All rights reserved. Microsoft is either a registered trademark or trademark of Microsoft Corporation in the United States and/or other countries. The names of actual companies and products mentioned herein may be the trademarks of their respective owners. Microsoft Virtual Academy Student Manual ii

3 Contents CONTENTS... III MODULE: CLOUD SERVICES AND VIRTUAL MACHINE AVAILABILITY... 4 Module Video Transcript... 4 Microsoft Virtual Academy Student Manual iii

4 Module: Cloud Services and Virtual Machine Availability Module Video Transcript Welcome to the Microsoft Virtual Academy course; Overview of Windows Azure Virtual Machines. This is module three; Cloud Services and Virtual Machine Availability. In this module we will outline what Windows Azure Cloud Services are, as well as roles and instances and how they are leveraged within Virtual Machines. We will also cover Windows Azure Service level agreements and availability features including fault and update domains, as well as Virtual Machine availability sets. Now I want to clarify something that you might run in to when you are using the portal, and that s to explain the difference between a Virtual Machine and a Cloud Service. If you had listened to our marketing messages, we kind of position Cloud services, the platform as a service, way to group things. And Virtual Machines are the infrastructures of service. When in fact Cloud service really is just a container, and when you create a standalone virtual machine, I ll explain what happens with respect to Cloud services. Here, let s switch back to the demo machine because I am going to go ahead and spin up a new VM to demonstrate what I am talking about in the next few slides. This 16 terabyte Virtual Machine you will notice that it is part of A URL, teched2012iaas.cloudapp.net. If I go to Cloud services, I don t see teched2012iaas. And that s because I created that as a standalone Virtual Machine. What I am going to do is create another Virtual Machine and in this one I will go ahead and create a Linux machine. Linux demo. Create a, give it a standard User account. See if I can match the passwords this time and it looks like I did. Press next and now I get asked that question do I want to create it standalone, or add to an existing one? This point I am going to add it to that 16 terabyte VM. So that s going to take a few minutes to create. Microsoft Virtual Academy Student Manual 4

5 In the meantime let me explain what s going to happen underneath the hood. Let me go back to the slides. When you create a Cloud Service using Visual Studio with Web and Worker roles, you get a configuration like this. We have got a Web role, it s got a number of VMs, instances underneath it that are PasS instances. We have got a Worker role, it s got a number of VMs that are PaaS instances as well, and wrapped around them is a Cloud Service. When you, it s so, the roles and instances. Now when, I, you create a standalone VM like that 16 terabyte VM that you saw in the portal You see standalone VM you don t see Cloud Service but there is an implicit Cloud Service that isn t exposed to you, just because we wanted to make it really easy for somebody to come to the portal that doesn t know anything about Cloud Services and be able to create a Virtual Machine without having to be confronted with, okay now there s a Virtual Machine and now there is a Cloud Service But there is an implicit one underneath the covers. When you add a second VM like I just did with that Linux VM that I created and it connected it to that existing VM, now the Cloud surface, service is going to surface for you because that s the grouping concept we have got. So, let me, before we flip back let me see if it s showed up. Yep, let s flip back to the demo machine. Already, and I think this Linux VM is still being provisioned, you can see this initializing, but you can see that now in Cloud Service, that teched2012iaas showed up. That was the DNS name for that standalone Virtual Machine, which doubles as the, as the Cloud Service name. Because Cloud Service names map directly to the DNS name that you get in Windows Azure by default, of course you can bring your own DNS name, but now that was the Virtual Machine that I used as the baseline that I added the other Virtual Machine to, so that s the default Cloudapp name for this new Cloud Service. Or this Cloud Service that now just made its appearance. And this Virtual Machine, is still starting up, so we ll come back to that in a minute and I ll explain Or I ll demonstrate what Cloud Services gets you. Let s go back to the slides. This grouping besides being something that makes it possible to manage multiple VMs at the same time, so I can delete them at the same time and I get a build that shows me what is going on with that Cloud Service. It also, is a Virtual network boundary. So, those Virtual Machines can see each other and by default Cloud Services can t see each other, other than through the public IP addresses that they are given. Microsoft Virtual Academy Student Manual 5

6 When you put the VMs together, wrap them in a Cloud Service, now they re on a Virtual private network. So they can see each other without having to go through their public IP addresses. And now let me see if this is ready for us to show a quick demo of that in action. Yeh. Nope, it s still booting up. The Linux machine is booting and it ll be ready in a few seconds. What we are going to when I, this is ready and I might just wait until we get to the Virtual networking part to show this concept at play, is that I ll be able to ping the Windows machine from the Linux machine because they are part of the same Cloud Service using the internal IP address. Whereas somebody else in a different IP add, in a different Cloud Service, another Virtual Machine, can t see those IP, those internal IP addresses because they are blocked by the Virtual networking firewalls that we create in the infrastructure. OK let s go back to the slides. Oh, we are on the slides. So that s the demo I just walked through. And like I said, I ll come back and show you that ping in a second. Let s talk about Virtual Machine availability now. So when it comes to our SLAs [Service Level Agreements], if you go and read our public SLA document it says that we offer a per cent connectivity SLA to your front ends of your Cloud Service. And what that means is that Cloud Service, to get that SLA, needs to have at least two instances in it. So for example, two Web roles sitting on behind port 80, behind the load balancer, we re guaranteeing per cent of the time you will be able to hit one of those two instances. What that does is make a contract with you about our planned and unplanned outages. First of all the unplanned outages happen for obvious reasons, disks going bad, memory going bad, and network NICs going bad, and all sorts of hardware failures that can take place when you have got a datacenter. It also makes a contract with you for planned outages. We are running Windows Server Hyper-V underneath our fabric and that means that we would need to patch it to be secure. We also patch it to fix reliability issues. Or, improve performance. And so we do this patching, you can guess about how often we do it. It s about as often as you are doing it. Microsoft Virtual Academy Student Manual 6

7 Which should be once a month. You can guess about what time of the month we are doing it. And, what, when that happens we roll through the datacenter s and we honor our SLA using a concept called Update domains. And, we honor the contract with you about faults or failures or hardware using something called fault domains. So, where am I going with this? Well with single multi-instance PaaS applications, we offer this We wanted to offer something for single instance machines too. If you take the and you say what does that imply about a single instance, it s Now that s not a very round number, it s actually not a number that people really like. People when they talk about SLAs like to talk about number of nines, and so we decided to go with a number of nines and say that our single instance SLAs are going to be 99.9 per cent. We are in preview right now so we don t really offer a SLA on our single instances when we go to general availability this is what you should expect. I flipped this on upside down. There we go. So 99.9 per cent. That s about eight and a half hours of down time a year, so that s down time, more down time than some people would like for their more important applications. So that is where something called availability sets come in, which lets you take multiple virtual machines and wrap this concept of fault domains and update domains on top of them. Now what s a fault domain and what s an update domain? And by the way that lets you get the same per cent availability that you get for our PaaS services. But what s a fault domain and what s an update domain? A fault domain represents single points of failure in the datacenter. And an update domain tells us a) if you have got a pass service how, we roll updates that you give us out to those instances that are part of a role. And b) what order we service this, the servers in the datacenter, so that we can guarantee that we don t take down VMs from more than one update domain of your role at a time. So let s take a deeper look at, of this update domain and fault domain concept by taking a look at how they map onto a Cloud service, a PAZ Cloud Service. You can see I have got a Web role, it s got four instances. Microsoft Virtual Academy Student Manual 7

8 I ve got a Worker role that s got four instances. And, we, by default you get two fault domains, for any role, so we will spread these four instances across at least two single points of failure in the datacenter. And you also get a number of update domains by default you get five update domains. You can ask for up to 20. And this means that we will never take down for planned outage whether it is us serving the server underneath or you deploying an update to this, more than that number of update domains, more than that number of machines, number of instances divided by number of update domains at a time. So, in this case let s say that we have got racks, we will deploy this thing to two different racks, to spread it across at least two fault domains. We always try and spread it across at least more than two, but that s our guarantee. So rack is a fault domain because there s a top of rack router on the top that s not redundant, so if that thing fails then we lose connectivity to the whole rack. And then we also map update domains to match the fault domains and so you can see we ve got two fault update domains here. We could have had more if we had wanted to, but two update domains means that when we roll a host OS update out through the datacenter, that we will take down update domain one, re-boot it, make sure that it comes up healthy, and then move on and service the servers under update domain two. Same thing when you apply an update to the Web role, it ll apply to update domain one, once the, that, those, that domain is healthy then we ll move on to update domain two. So availability sets lets you take that update domain fault domain concept and apply it to arbitrary virtual machines. A virtual machine underneath the hood is really a single instance role, so this is taking those role concepts that we have for PaaS, lifting them off and letting you basically create IAAS roles out of multiple virtual machines. So here, I wrapped these two tiers into availability sets. I ve basically created the equivalent of the Web and Worker role from the availability, from a fault domain update domain perspective. And so that means that we will spread them across at least two fault domains and we will put them in different update domains. So now when we serve, service the host OS, you will see we will only take down one of these at a time. So this allows you to get high availability, the per cent SLA, and when we are servicing the host OS, 100 per cent availability through that kind of operation for a tier that you ve scaled, deployed in this manner. Let s go to... What just Oh, here we go. Microsoft Virtual Academy Student Manual 8

9 So let s go back to the demo machine and I m going to show you, how this app that I have got here, this Cloud Service right here The fabrikam-cloudapps. If we take a look at underneath the hood of it, it consists of four VMs just like I had in the slide. These two front end, webappsmgr1 and webappsmgr2... Two back ends, SQL1 and SQL2. And if I click on the front end And go to configure, you can see I put these front ends in availability set, so again I get that per cent SLA for the front end, from a fault domain and update domain perspective. Microsoft Virtual Academy Student Manual 9