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Hello,
Our application is hosted on a Docker container, which is running on an Azure Web App.
We have a custom domain, and we've modified it at the custom domain level of the web app. However, the environment variable WEBSITE_HOSTNAME still contains the default host in '.azurewebsite'.
Is it possible to modify and replace it with the custom domain host?
Regards,
WEBSITE_HOSTNAME is a read-only environment variable that cannot be changed by the end user. You can refer to the App environment table for a complete list of environment variables that are read-only.
Yes. Refer to Map existing custom DNS name - Azure App Service | Microsoft Learn for the steps on assigning a custom domain to your app service. It's preferred to add a CNAME DNS record over an A record should you scale or move your app.
Hello @Ryan Hill
I have already performed these steps, but the default domain is still the one ending with .azurewebsite.
I would like to do this because the health check is showing 00%, and the monitoring send alerts to the support team.
In the app settings, we use the custom host to communicate with the database, we have WordPress as the back office.
This phenomenon occurred at the moment of activating the custom domain, and the health check is performed on the environment variable WEBSITE_HOSTNAME, which is read-only.
I check Log for the web app, the helath check return 401 and use the custom domain to check it.
Do you have any idea how to resolve this while keeping the health check enabled?
Regards,
The default domain will always be *.azurewebsites.net. If you enter your custom domain in a tool like https://dnspropagation.net/ as the CNAME or https://www.digwebinterface.com/ as your hostname, it should show www.yourdomain.com pointing to appname.azurewebsites.net. The health check endpoint should always start with /. If you configured the health check as www.yourdomain.com, which I don't believe is possible, then this won't work because health check is meant for checking the instances of workers behind the Front-End.
Furthermore, the health checks will now show in AppServiceHTTPLogs table. If you wish to log this request, then you would place console log message in your health check endpoint and check AppServiceConsoleLogs table or use the Health Check metrics available in Azure Monitor.
Hello Ryan Hill
I don't understand your response. It seems like you reiterated what I mentioned in my previous comment.
As shown in the logs in my previous comment, the healthcheck test is directed towards the custom_hostname.
Is it possible to change this, or how can I resolve my healthcheck to make it Healthy100%?
Regards,
Change your health check endpoint so that it's pointed to /, e.g., /status, /api/health, etc. in the Health Check blade under your app service. You can also use
$resourceGroupName = "resourcegroupname"
$appName = "webappname"
$webApp = Get-AzWebApp -ResourceGroupName $resourceGroupName -Name $appName -ErrorAction Stop
# enable healthcheck feature. Update healthcheckpath
$webApp.SiteConfig.healthCheckPath = "/healthcheckpath"
# Saving new configuration
$webApp = Set-AzWebApp -WebApp $webApp -ErrorAction Stop
or
az webapp config appsettings set -g ResourceGroupName -n AppServiceName --subscription SubscriptionID --settings WEBSITE_HEALTHCHECK_MAXPINGFAILURES=7
az webapp config set -g ResourceGroupName -n AppServiceName --generic-configurations "{\"healthCheckPath\": \"/api/health/\"}"
Let me know if this doesn't help.