Monitor an App Service app with web server logs using Azure CLI

Article
04/26/2022
3 minutes to read

This sample script creates a resource group, App Service plan, and app, and configures the app to enable web server logs. It then downloads the log files for review.

If you don't have an Azure subscription, create an Azure free account before you begin.

Prerequisites

Use the Bash environment in Azure Cloud Shell. For more information, see Azure Cloud Shell Quickstart - Bash.
If you prefer to run CLI reference commands locally, install the Azure CLI. If you are running on Windows or macOS, consider running Azure CLI in a Docker container. For more information, see How to run the Azure CLI in a Docker container.
- If you're using a local installation, sign in to the Azure CLI by using the az login command. To finish the authentication process, follow the steps displayed in your terminal. For additional sign-in options, see Sign in with the Azure CLI.
- When you're prompted, install Azure CLI extensions on first use. For more information about extensions, see Use extensions with the Azure CLI.
- Run az version to find the version and dependent libraries that are installed. To upgrade to the latest version, run az upgrade.

Sample script

Launch Azure Cloud Shell

The Azure Cloud Shell is a free interactive shell that you can use to run the steps in this article. It has common Azure tools preinstalled and configured to use with your account.

To open the Cloud Shell, just select Try it from the upper right corner of a code block. You can also launch Cloud Shell in a separate browser tab by going to https://shell.azure.com.

When Cloud Shell opens, verify that Bash is selected for your environment. Subsequent sessions will use Azure CLI in a Bash environment, Select Copy to copy the blocks of code, paste it into the Cloud Shell, and press Enter to run it.

Cloud Shell is automatically authenticated under the initial account signed-in with. Use the following script to sign in using a different subscription, replacing <Subscription ID> with your Azure Subscription ID. If you don't have an Azure subscription, create an Azure free account before you begin.

subscription="<subscriptionId>" # add subscription here

az account set -s $subscription # ...or use 'az login'

For more information, see set active subscription or log in interactively

Run the script

# Monitor an App Service app with web server logs
# set -e # exit if error
# Variable block
let "randomIdentifier=$RANDOM*$RANDOM"
location="East US"
resourceGroup="msdocs-app-service-rg-$randomIdentifier"
tag="monitor-with-logs.sh"
appServicePlan="msdocs-app-service-plan-$randomIdentifier"
webapp="msdocs-web-app-$randomIdentifier"

# Create a resource group.
echo "Creating $resourceGroup in "$location"..."
az group create --name $resourceGroup --location "$location" --tag $tag

# Create an App Service Plan
echo "Creating $appServicePlan"
az appservice plan create --name $appServicePlan --resource-group $resourceGroup

# Create a Web App and save the URL
echo "Creating $webapp"
url=$(az webapp create --name $webapp --resource-group $resourceGroup --plan $appServicePlan --query defaultHostName | sed -e 's/^"//' -e 's/"$//')

# Enable all logging options for the Web App
az webapp log config --name $webapp --resource-group $resourceGroup --application-logging azureblobstorage --detailed-error-messages true --failed-request-tracing true --web-server-logging filesystem

# Create a Web Server Log
curl -s -L $url/404

# Download the log files for review
az webapp log download --name $webapp --resource-group $resourceGroup

Clean up resources

Use the following command to remove the resource group and all resources associated with it using the az group delete command - unless you have an ongoing need for these resources. Some of these resources may take a while to create, as well as to delete.

az group delete --name $resourceGroup

Sample reference

This script uses the following commands to create a resource group, App Service app, and all related resources. Each command in the table links to command specific documentation.

Command	Notes
`az group create`	Creates a resource group in which all resources are stored.
`az appservice plan create`	Creates an App Service plan.
`az webapp create`	Creates an App Service app.
`az webapp log config`	Configures which logs an App Service app persists.
`az webapp log download`	Downloads the logs of an App Service app to your local machine.

Next steps

For more information on the Azure CLI, see Azure CLI documentation.

Additional App Service CLI script samples can be found in the Azure App Service documentation.