Occasionally, there are times when a system needs to undergo maintenance for a short time. Standard Web Apps handle this by redirecting all traffic to an app_offline.htm if the file exists in the root directory (wwwroot). What is the equivalent for a Linux Web App for Containers instance?
I tried using Kudu's Bash terminal by echoing the minimum html contents into an app_offline.htm but it isn't working.
One thing I was looking into would be having a specific container image that is for maintenance, but that doesn't seem very elegant.
Eventually, I would like to be able to automate this via Azure DevOps.
Are you able to create an app setting with the name SCM_CREATE_APP_OFFLINE and a value of 1 to see if this allows the creation of a app_offline.htm file?
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I have successfully set up Jenkins on local domain as a test. It builds from SCM, zips the build, extracts to a unique timestamp folder, and then copies over the files to the IIS folder.
I now have to set it up to deploy to a Azure VM. Now things are getting hairy.
I get the file to copy across - it takes a long time. Unzipping literally takes an hour.
Cross domain user rights are also making things difficult as the user running Jenkins service does not exist on production boxes which are on Azure domains.
What are my options?
Should I install a slave node on the production box and then "activate" the slave from the master and then let the slave :
1. perhaps copy the file over from Azure storage to the production box?
2. extract the files
3. Copy the files to the IIS folder.
Well, there's no clear answer to this, try what works best for you. So the main options i see are:
1. Use slave node in Azure, upload zip to some place (Azure storage account or whatever) and let slave node handle the download\unpacking\etc.
2. Use remote PowerShell and connect directly to servers in Azure and download the zip from the web (or Azure storage or whatever) and extract it.
3. Use a tool, like Octopus, which does literally the same, but is kind of build with deployments in mind.
I have just deployed the basic NodeJS express app on Google Cloud Platform from IntelliJ IDEA. However I cannot find and browse the source files. I have searched in the Development tab, App Engine tab and it shows the project but not the actual files. I can access the application from my browser and it is running fine. I can see the activity and requests everything coming into the application but I cannot see the source files. I tried searching for them in the terminal Google Cloud Console and I cannot locate the files in there either. It's puzzling because I don't know where the files are being served from.
AFAIK seeing the live app code/static content directly in the developer console is not possible (at least not yet), not even for the standard environment apps.
For apps using the flexible environment (that includes node.js apps) accessing the live app source code may be even more complex as what's actually executed on GAE is a container image/docker file (as opposed to plain app code source file from a standard environment app). From Deploying your program:
Deploy your app using the gcloud app deploy command. This command
automatically builds a container image for you by using the Container
Builder service (Beta) before deploying the image to the App
Engine flexible environment control plane. The container will include
any local modifications you've made to the runtime image.
Since the container images are fundamentally dockerfiles it might be possible to extract their content using the docker export command:
Usage: docker export [OPTIONS] CONTAINER
Export a container's filesystem as a tar archive
Options:
--help Print usage
-o, --output string Write to a file, instead of STDOUT
The docker export command does not export the contents of volumes
associated with the container. If a volume is mounted on top of an
existing directory in the container, docker export will export the
contents of the underlying directory, not the contents of the
volume.
One way of checking the exact structure of the deployed app (at least in the standard environment) is to download the app code and check it locally - may be useful if suspected incorrect app deployment puts a question mark on the local app development repository from where deployment originated. Not sure if this is possible with the flexible environment, tho.
The accepted answer to the recent Deploy webapp on GAE then do changes online from GAE console post appears to indicate that reading and maybe even modifying live app code might be possible (but I didn't try it myself and it's not clear if it would also work for the flexible environment).
We have an Website project that's hosted in Azure, and we use Web.config transforms for setting environment variables. However, our current approach for building the system for different environments is to build the project multiple times (currently this is 3), which is inefficient.
We'd like to move to using Web Deploy, as this would then set us up nicely for using Release Manager.
Our issue is around using Web Deploy parameters instead of web.config transforms; we need to substitute multiple xml elements, rather than single values.
After much research, I found these 2 articles which detail almost exactly what I'm trying to do
http://blogs.iis.net/elliotth/web-deploy-xml-file-parameterization
http://www.iis.net/learn/publish/using-web-deploy/parameterization-improvements-in-web-deploy-v3
Essentially I'm trying to replicate Scenario 5, but using a separate Set Parameter file for the value.
Unfortunately, in the examples, referencing an external xml file only works if it is on the target machine. Some testing with a colleague confirmed this; works on local machine, but not on Azure.
Is there a way I can force Web Deploy to look in a particular location for the external configuration files?
As you've already noticed, Web Deploy is only able to read replacement values on the local machine or on a UNC share. It can't read that specific file over HTTP.
If you're deploying to an Azure Web App, then one thing you could try would be to use Kudu/FTP to manually upload that file one level above your wwwroot folder. Then you could specify the file location like so:
D:\home\site\prices.xml:://book[#name='book1']/price
Of course this implies that you'd have to pre-upload this file before publishing to your site, so it's not a perfect solution, but it should work for what you're trying to accomplish.
My Azure web app (App Service) writes a log file mywebapp.log to the d:\LogFiles directory of the VM that hosts the website. When the log file gets to a certain size I rename it to mywebapp1.log, mywebapp2.log, and so on so and a new log file is created. (I do this manually - stop the website, rename the file and restart the site.)
One day I inspected the directory through the Kudu (SCM) portal and saw just a lone mywebapp.log that was much larger than normal. The file included all of the individual logs that previously existed (included the contents of mywebapp1.log + mywebapp2.log and so on).
My app has no which combines the files. Is there an Azure process that does this or did I do it in my sleep and have no recollection?
There really is no logic in Azure that would do this. Azure knows nothing about your log files, and would not be doing anything with them, especially something as complex as combining several existing files into one.
So I'll go with the sleep theory on this one :)
The problem was that I had swapped deployment slots at some point and failed to realize that the d:\LogFiles directory (the entire d: drive I believe) travels with the slot. The missing log files were sitting in my staging slot's LogFiles directory.
I have a brilliantly designed app_offline.htm file that I'd like to display on my site periodically when I'm doing things like backing up the DB. On a server with a real file system, this wouldn't be a problem: I'd just copy app_offline.htm to the my app's root, and IIS will work its magic and redirect all requests to this file.
However, I'm using Azure, so there's no real file system and there's no easy way move files around from one location to another.
How I can I make app_offline.htm play nicely with Azure?
I figured I'd add this, I haven't seen it mentioned yet. You can actually do this via web publish from Visual Studio (or WebMatrix) as well, just put app_offline.htm in the root of your project - the same level as your main web.config. When done, just rename it and redeploy to go back online. 2 clicks - easy.
The manual option is to drop it into your /site/wwwroot via FTP.
A little personal secret, none of your site files will be accessible, style sheets etc. So put your includes into an azure blob container, and viola.
Actually there is a real file system, as each VM instance runs on Windows 2008 Server (SP2 or R2 SP1). To see this for yourself, enable Remote Desktop for your deployment and connect to a running instance.
Knowing this, you should be able to set up a mechanism to perform a file-copy of your app_offline.htm to your app root based on some type of administrative command. You'll just need to make sure each of your web role instances perform this action.
David has provided you with a good answer. However, you might be missing out on what Azure can do for you. You should be able to virtually eliminate down time with Azure by running multiple instances and using SQL Azure which is triple backed up for you. You can also backup SQL Azure using http://msdn.microsoft.com/en-us/library/ff951624.aspx