I am using an Azure WebApp with development slots running a netcore aspnet install. How often are these instances patched and how are they patched?
Is there any way for me to see a log of exactly when they are patched?
If you are referring to the app itself in Azure App Service when you deploy a Web App from the gallery you get an install of whatever item you selected. That item will not be automatically updated, if they try to update the container this will most likely break your application especially if you had customized that container in any way.
If you are referring to the OS, Microsoft will update the OS and IIS version from time to time and when they do, if there is any possibility of this affecting your app there will be an e-mail sent to the e-mail account registered under the subscription notifying him/her of the maintenance. Normally you shouldn't experience any downtime.
You may also check the Operating system functionality on Azure App Service and Kudu Console for more details.
Hope this helps.
Related
Today, I checked my windows azure website (built with a web service) And the version was not the same as yesterday. It's very strange, it seems that ther version went backward.
So I took my project in VS and reuploaded it. Then it was good
I am quite scared, is it a normal behaviour, I think not. But how to stop this behaviour. If I remember well it's not the first time it happens to my project.
Thanks a lot for your help.
Internally if there is any problem within Azure, It is the nature of Azure to Remove the troublesome VMs and Deploy a new VM with the "cspkg" File that we upload during application deployment either through Azure portal or through Visual studio directly.
In case You make any changes through RDP to the deployed application, there is no guarantee that the application will retain the Changes.
Further more if you face this again, it is better to contact Microsoft Support, They should help you out.
Here is the explanation of the Microsoft Support :
Any changes made with Web Deploy are temporary. It can only be used for development and testing and not intended for updating applications in production. When the role instance is restarted, the changes will be gone. We would suggest that you upgrade the deployment by uploading package files from the management portal or disabling WebDeploy while deploying.
You can read more about Web Deploy here http://blogs.msdn.com/b/cloud/archive/2011/04/19/enabling-web-deploy-for-windows-azure-web-roles-with-visual-studio.aspx.
I've created an Azure server instance. I've deployed a simple application to it. As part of the deployment process I enabled Remote Desktop Connections.
I have some standard ASP.net applications that run on Windows, is there something to stop me deploying these applications manually to IIS using Remote Desktop. I've read so much about having to migrate standard ASP.net apps to Azure. I don't want to this as we will have customers who will still use Windows Server 2003/2008 so I don't want to have to maintain 2 versions.
Well, as I understand it, in theory you could deploy stuff using remote desktop. But when the instance shuts down/restarts you'll lose it all (unless you've built it into your startup scripts) and have to re-load everything each time. The main reason they suggest you have at least two instances is so that when one shuts down for updates etc there is always at least one other running.
The "Windows Azure Accelerator for Web Roles" project allows you to create an Azure web role which then enables you to use web deploy for all your other web sites - I'm guessing that will be a whole lot better approach and is definitely worth a look. Also, I believe smarx.com is a good place to browse for info and ideas.
Using a startup task and the Azure Bootstrapper you can download, unzip, install almost any kind of 3rd party software that supports either xcopy deployment (just copy the files) or an unattended(silent) install.
Assuming you aren't using Azure storage or anything like that, there shouldn't be any difference with the IIS application. If you are using anything specific to Azure, you can use the RoleEnvironment.IsAvailable to test if you are running inside Azure or not. That will return true for the emulator as well. If you want to use Azure storage from both, you can add the settings in the web.config to use if not running in Azure.
I currently work with a legacy asp.net web application and one of the requirements going forward is that it be deployable to windows azure.
I would like to know how difficult it will be to manage deployment to both Azure and a traditional IIS web server.
Azure seems to require a specific customized version of a web applicaiton project is it possible to deploy the customized web application to a standard IIS instance once it has been converted.
EDIT:
It is a ASP.NET Web Application rather than a Web Site (compiles everything into one dll)
UPDATE:
In the end due to the amount of work involved in converting the application to work in Azure and the cost of Azure compared with other cloud solutions it was decided to go with a traditional Cloud hosted virtual server.
And thank you for the really good answers.
Whether or not you can deploy your application to Azure almost as is depends a lot on how your application works. Azure pretty much requires your application be stateless. If it's a plain vanilla web application that stores data in the session or application cache only and saves data to a database only, then you can deploy it to Azure.
If you have stateful services running like background threads (which is bad anyways), or if you save data to the file system (besides temporary caching), then you may have issues. Really, the issues moving to Azure are really the same as moving to any multi-server load balanced solution. One caveat is permanent storage.
If you need to store data in a place other than the database, then you're best off working with Azure's storage solution which has an API and client library for storing binary data, key/value data (they call it tables, but really, it's not tables), and queues. They also do have a transparent blob-as-file-system option for compatibility. If you want to use these in your app that also is used outside of Azure then you need to write an extra layer between your code and the Azure client library that supports both Azure services and standard local service. Azure SDK does include emulators for Azure services, but they're definitely not meant for production use.
As far as the mechanics of Azure-specific projects, that is actually not that difficult. Yes, you need to create an Azure-specific project in your solution that defines the Web Role and what gets deployed, but it will reference your existing Web Application, not the other way around. You can deploy the Azure Web Role to Azure or you can continue to deploy the existing application to IIS normally and concurrently.
Web Site, Web Application, MVC, really doesn't make much of a difference. Actually doesn't have to be .NET either. Can be PHP or Java or whatever you want to put on your VM. It'll all work the same as far as Azure is concerned.
MS likes to push Azure as a Platform-as-a-Service (Paas) solution where they have a ton of services they offer and you run apps on their standard platform, and contrasts that with Amazon AWS which they call Infrastructure-as-a-Service (Iaas) which is "just" a Virtual Machine. However, MS is really just as much a IaaS solution as AWS, perhaps even more so. The only difference between AWS and Azure is AWS allows you to choose what to install on your VM and with Azure you have to use Windows Server 2008 R2 as the basis for your VM (but you can customize the VM image to install custom software on top of windows). With both Azure and AWS, the hosts offer additional PaaS services you can take advantage of for data storage and message routing. AWS also offers tons of extra services like video streaming.
Also note that with Azure (and AWS I think) you can use the services they offer even in a non-hosted application. If you want to use Azure's data storage from a non-Azure application, you can do that, it's just HTTP REST calls to get/put data. The only differences you pay for data in/out between datacenter and your non-datacenter-hosted application which would be free if the app was also inside the datacenter (just the data in/out is free in-datacenter, you still have storage and transaction fees).
A few things:
Samuel Neff's answer mentioned mounting a file system in a blob (a Cloud Drive). Only one instance may lock this cloud drive for writing, so it does not behave like a network file share. You'll need to plan for this.
You'll need to integrate with the Windows Azure diagnostics subsystem, to gain visibility into your app's run state (e.g. performance counters, trace logs, etc.).
If there are 3rd-party apps that your web app depends on, you'll need to install these. These actually get installed as part of the role instance's boot process, either via your OnStart() event handler or as a startup task. The latter allows for admin-level installs (including registry changes, COM component installations, etc.). You'll need to carefully manage these installations, as they impact the boot time of the instance.
For an asp.net app, you'll need to think about session state. In-proc session state won't work, because each instance will have its own state store in memory. The SQL Azure session state provider doesn't have background cleanup agents, so you'll need to build this into your web or worker role instance (see this blog post by the SQL Azure team for the implementation). The best option is to use the AppFabric Cache, a new service that just went into production. This cache-as-a-service provides an custom session state provider for asp.net as well. Note: As of today, the AppFabric Cache service is only accessible via a .NET interface; there's no REST interface for it (all other storage services - tables, blobs, queues - have a REST interface). .NET, Java, and PHP all have storage client libraries. Ruby has one from the open source community.
You'll have to manage scaling out to more than one instance, when the need arises. This is not a built-in service today, but there are 3rd-party services such as ParaLeap's AzureWatch. There's also Microsoft's System Center Operations Manager, which now has Windows Azure monitoring support. You'll also need to handle scale-back situations, where you reduce the number of server instances.
I have some additional details in an answer for a similar StackOverflow question, here.
I have not tried Windows Azure Migration Scanner personally, but if it works as advertised, this would really come in handy.
Usually I would look at writing a Windows Service to manage tasks that aren't suited to being hosted in a web application. These types of tasks are usually long running processes or scheduled tasks. Although this is normally the primary approach for these types of tasks, people have looked at ways of running these kinds of background processes in a web application by kicking off a number of threads in the Application_Start event exposed by Global.asax. The problem with this approach has always been that if your IIS worker process dies, then your background thread is killed too (effectively your 'Windows Service' is stopped until the next request is received).
ASP .NET 4.0 offers a solution to this problem. You can now set the StartMode to 'AlwaysRunning' as described in this blog post by Scott Gu. Somewhere in the comments on this post, someone asks a question about the viability of hosting Windows Service type tasks in IIS since the new feature ensures the worker process is always running. Scott mentioned that it would definitely support the scenario. Further to this, the recent introduction of AppFabric means that Microsoft themselves are providing simple hooks for hosting and monitoring WCF and WF services in a web application.
What does this mean for those of us that used to write Windows Services to support our web apps? Should we adopt this model? What are the pitfalls? As far as I can tell, there are a number of benefits to hosting 'Windows Service' processes in a web application, the most useful being the ease of deployment. Furthermore, we can actually start developing simple user interfaces to our services which provide information about what is happening at runtime.
If I had to go this route, I don't think that I would host my 'Windows Service' type functionality in the customer facing web application. I would probably develop a new web application project (much like I would in the Windows Service context) that would host my long running/scheduled task processes. I guess there are few reasons for this.
Security. There may be a different security model for the UI displaying information about the running background processes. I would not want to expose this UI to anyone else but the ops team. Also, the web application may run as a different user which has an elevated set of permissions.
Maintenance. It would be great to be able to deploy changes to the application hosting the background processes without impacting on user's using the front end website.
Performance. Having the application separated from the main site processing user requests means that background threads will not diminish IIS's capability to handle the incoming request queue. Furthermore, the application processing the background tasks could be deployed to a separate server if required.
I would be really interested to hear your thoughts on this approach and whether I should be sticking with Windows Services. I am very tempted to try this new approach.
What does this mean for those of us that used to write Windows Services to support our web apps?
I think this a key scenario where you could be move away from a Windows service to using the continous running web site.
Should we adopt this model?
Standard development answer: Depends ;)
What are the pitfalls?
One issue I can see is the IIS dependency. If you need a service to run on a users machine I would not feel comfortable about asking them to install IIS just to run my service. Here I think the traditional model works better.
Monitoring and tracking are major issues, but as you also point out this is solved by AppFabric. It is even better than what you get from the Window Service. However you have added another dependency which also will require .NET 4.0 and a relatively new version of Windows. I could also be wrong here, but my understanding is that AppFabric is not supported in production on client OS's. Which could bring in additional headaches.
You will lose pause functionality in the continuous web site model too.
Finally IIS killing inactive app-pools isn't the only way an app pool can recycle. Editing a web.config file causes it for instance, which may not be an ideal situation.
the most useful being the ease of deployment.
I also think development is much easier - in the past I have had a console app and a windows service so I can dev/test on my machine using the console app and then change it to a windows service when it goes out. Now dev/test is MUCH easier.
A must read for this is Death to Windows Services...Long Live AppFabric!
What are the pitfalls?
One I found, no shutdown event. You have AppStart when the web site starts (not global.asax because that is HTTP only) but you have no way to handle shutdown which could mean disposing becomes an issue.
I would suggest sticking with a windows service. The issue is with your number 2.
You won't be able to update service part of web site without restarting whole web site.
Im looking at writing a application for a web 2.0 start up site which will essential monitor specific RSS feeds.
Due to the expected up take of such a service I am expecting that taking advantage of cloud computing would be the way to do it, however with my lack of experience I do not know if it is possible to run a Windows service in the cloud.
There will be a web front end to this but it isn't imagined that that will have a heavy load as it will be just for sign up, then users will recevie notifications by SMS/Email
You can run a "service" in the cloud, when using Azure. It's called a "Worker Role" see the Architecture here.
If you're looking at running Windows Azure (which splits into a web role and worker role).
You'll have to sign up for an Azure key (The Bizspark pack includes one I believe) to get started, download the SDK and Azure tools.
It looks like you would only really need the web role for this, in which case it's just a normal ASP.NET / MVC site that you'd write as normal.
Essentially the benefit you'd get here would be being able to ramp up the number of server instances running your application by tweaking the config file.
The other option is the Amazon EC2 Cloud which allows you to instantiate as many instances of Windows2k3 Data Centre edition as you need. I run Windows Services, IIS, Postgresql etc. on such an instance with no issues.
Managed to find this link to publishing WCF services in the cloud. Im new to WCF so not sure if it will offer the solution I require, it probably will but I need to do some more research
Link