Backend health and diagnostic logs - Azure Application Gateway (2024)

  • Article
  • 13 minutes to read

You can monitor Azure Application Gateway resources in the following ways:

  • Backend health: Application Gateway provides the capability to monitor the health of the servers in the backend pools through the Azure portal and through PowerShell. You can also find the health of the backend pools through the performance diagnostic logs.

  • Logs: Logs allow for performance, access, and other data to be saved or consumed from a resource for monitoring purposes.

  • Metrics: Application Gateway has several metrics which help you verify that your system is performing as expected.

Note

We recommend that you use the Azure Az PowerShell module to interact with Azure. See Install Azure PowerShell to get started. To learn how to migrate to the Az PowerShell module, see Migrate Azure PowerShell from AzureRM to Az.

Backend health

Application Gateway provides the capability to monitor the health of individual members of the backend pools through the portal, PowerShell, and the command-line interface (CLI). You can also find an aggregated health summary of backend pools through the performance diagnostic logs.

The backend health report reflects the output of the Application Gateway health probe to the backend instances. When probing is successful and the back end can receive traffic, it's considered healthy. Otherwise, it's considered unhealthy.

Important

If there is a network security group (NSG) on an Application Gateway subnet, open port ranges 65503-65534 for v1 SKUs, and 65200-65535 for v2 SKUs on the Application Gateway subnet for inbound traffic. This port range is required for Azure infrastructure communication. They are protected (locked down) by Azure certificates. Without proper certificates, external entities, including the customers of those gateways, won't be able to initiate any changes on those endpoints.

View backend health through the portal

In the portal, backend health is provided automatically. In an existing application gateway, select Monitoring > Backend health.

Each member in the backend pool is listed on this page (whether it's a NIC, IP, or FQDN). Backend pool name, port, backend HTTP settings name, and health status are shown. Valid values for health status are Healthy, Unhealthy, and Unknown.

Note

If you see a backend health status of Unknown, ensure that access to the back end is not blocked by an NSG rule, a user-defined route (UDR), or a custom DNS in the virtual network.

Backend health and diagnostic logs - Azure Application Gateway (1)

View backend health through PowerShell

The following PowerShell code shows how to view backend health by using the Get-AzApplicationGatewayBackendHealth cmdlet:

Get-AzApplicationGatewayBackendHealth -Name ApplicationGateway1 -ResourceGroupName Contoso

View backend health through Azure CLI

az network application-gateway show-backend-health --resource-group AdatumAppGatewayRG --name AdatumAppGateway

Results

The following snippet shows an example of the response:

{"BackendAddressPool": { "Id": "/subscriptions/00000000-0000-0000-000000000000/resourceGroups/ContosoRG/providers/Microsoft.Network/applicationGateways/applicationGateway1/backendAddressPools/appGatewayBackendPool"},"BackendHttpSettingsCollection": [ { "BackendHttpSettings": { "Id": "/00000000-0000-0000-000000000000/resourceGroups/ContosoRG/providers/Microsoft.Network/applicationGateways/applicationGateway1/backendHttpSettingsCollection/appGatewayBackendHttpSettings" }, "Servers": [ { "Address": "hostname.westus.cloudapp.azure.com", "Health": "Healthy" }, { "Address": "hostname.westus.cloudapp.azure.com", "Health": "Healthy" } ] }]}

Diagnostic logs

You can use different types of logs in Azure to manage and troubleshoot application gateways. You can access some of these logs through the portal. All logs can be extracted from Azure Blob storage and viewed in different tools, such as Azure Monitor logs, Excel, and Power BI. You can learn more about the different types of logs from the following list:

  • Activity log: You can use Azure activity logs (formerly known as operational logs and audit logs) to view all operations that are submitted to your Azure subscription, and their status. Activity log entries are collected by default, and you can view them in the Azure portal.
  • Access log: You can use this log to view Application Gateway access patterns and analyze important information. This includes the caller's IP, requested URL, response latency, return code, and bytes in and out. An access log is collected every 60 seconds. This log contains one record per instance of Application Gateway. The Application Gateway instance is identified by the instanceId property.
  • Performance log: You can use this log to view how Application Gateway instances are performing. This log captures performance information for each instance, including total requests served, throughput in bytes, total requests served, failed request count, and healthy and unhealthy backend instance count. A performance log is collected every 60 seconds. The Performance log is available only for the v1 SKU. For the v2 SKU, use Metrics for performance data.
  • Firewall log: You can use this log to view the requests that are logged through either detection or prevention mode of an application gateway that is configured with the web application firewall. Firewall logs are collected every 60 seconds.

Note

Logs are available only for resources deployed in the Azure Resource Manager deployment model. You cannot use logs for resources in the classic deployment model. For a better understanding of the two models, see the Understanding Resource Manager deployment and classic deployment article.

You have three options for storing your logs:

  • Storage account: Storage accounts are best used for logs when logs are stored for a longer duration and reviewed when needed.
  • Event hubs: Event hubs are a great option for integrating with other security information and event management (SIEM) tools to get alerts on your resources.
  • Azure Monitor logs: Azure Monitor logs is best used for general real-time monitoring of your application or looking at trends.

Enable logging through PowerShell

Activity logging is automatically enabled for every Resource Manager resource. You must enable access and performance logging to start collecting the data available through those logs. To enable logging, use the following steps:

  1. Note your storage account's resource ID, where the log data is stored. This value is of the form: /subscriptions/<subscriptionId>/resourceGroups/<resource group name>/providers/Microsoft.Storage/storageAccounts/<storage account name>. You can use any storage account in your subscription. You can use the Azure portal to find this information.

  2. Note your application gateway's resource ID for which logging is enabled. This value is of the form: /subscriptions/<subscriptionId>/resourceGroups/<resource group name>/providers/Microsoft.Network/applicationGateways/<application gateway name>. You can use the portal to find this information.

  3. Enable diagnostic logging by using the following PowerShell cmdlet:

    Set-AzDiagnosticSetting -ResourceId /subscriptions/<subscriptionId>/resourceGroups/<resource group name>/providers/Microsoft.Network/applicationGateways/<application gateway name> -StorageAccountId /subscriptions/<subscriptionId>/resourceGroups/<resource group name>/providers/Microsoft.Storage/storageAccounts/<storage account name> -Enabled $true 

Tip

Activity logs do not require a separate storage account. The use of storage for access and performance logging incurs service charges.

Enable logging through the Azure portal

  1. In the Azure portal, find your resource and select Diagnostic settings.

    For Application Gateway, three logs are available:

    • Access log
    • Performance log
    • Firewall log
  2. To start collecting data, select Turn on diagnostics.

    Backend health and diagnostic logs - Azure Application Gateway (4)

  3. The Diagnostics settings page provides the settings for the diagnostic logs. In this example, Log Analytics stores the logs. You can also use event hubs and a storage account to save the diagnostic logs.

    Backend health and diagnostic logs - Azure Application Gateway (5)

  4. Type a name for the settings, confirm the settings, and select Save.

Activity log

Azure generates the activity log by default. The logs are preserved for 90 days in the Azure event logs store. Learn more about these logs by reading the View events and activity log article.

Access log

The access log is generated only if you've enabled it on each Application Gateway instance, as detailed in the preceding steps. The data is stored in the storage account that you specified when you enabled the logging. Each access of Application Gateway is logged in JSON format as shown below.

For Application Gateway and WAF v2 SKU

ValueDescription
instanceIdApplication Gateway instance that served the request.
clientIPIP of the immediate client of Application Gateway. If another proxy fronts your application gateway, this displays the IP of that fronting proxy.
httpMethodHTTP method used by the request.
requestUriURI of the received request.
UserAgentUser agent from the HTTP request header.
httpStatusHTTP status code returned to the client from Application Gateway.
httpVersionHTTP version of the request.
receivedBytesSize of packet received, in bytes.
sentBytesSize of packet sent, in bytes.
clientResponseTimeLength of time (in seconds) that it takes for the first byte of a client request to be processed and the first byte sent in the response to the client.
timeTakenLength of time (in seconds) that it takes for the first byte of a client request to be processed and its last-byte sent in the response to the client. It's important to note that the Time-Taken field usually includes the time that the request and response packets are traveling over the network.
WAFEvaluationTimeLength of time (in seconds) that it takes for the request to be processed by the WAF.
WAFModeValue can be either Detection or Prevention
transactionIdUnique identifier to correlate the request received from the client
sslEnabledWhether communication to the backend pools used TLS. Valid values are on and off.
sslCipherCipher suite being used for TLS communication (if TLS is enabled).
sslProtocolSSL/TLS protocol being used (if TLS is enabled).
serverRoutedThe backend server that application gateway routes the request to.
serverStatusHTTP status code of the backend server.
serverResponseLatencyLatency of the response (in seconds) from the backend server.
hostAddress listed in the host header of the request. If rewritten using header rewrite, this field contains the updated host name
originalRequestUriWithArgsThis field contains the original request URL
requestUriThis field contains the URL after the rewrite operation on Application Gateway
originalHostThis field contains the original request host name
{ "timeStamp": "2021-10-14T22:17:11+00:00", "resourceId": "/SUBSCRIPTIONS/{subscriptionId}/RESOURCEGROUPS/{resourceGroupName}/PROVIDERS/MICROSOFT.NETWORK/APPLICATIONGATEWAYS/{applicationGatewayName}", "listenerName": "HTTP-Listener", "ruleName": "Storage-Static-Rule", "backendPoolName": "StaticStorageAccount", "backendSettingName": "StorageStatic-HTTPS-Setting", "operationName": "ApplicationGatewayAccess", "category": "ApplicationGatewayAccessLog", "properties": { "instanceId": "appgw_2", "clientIP": "185.42.129.24", "clientPort": 45057, "httpMethod": "GET", "originalRequestUriWithArgs": "\/", "requestUri": "\/", "requestQuery": "", "userAgent": "Mozilla\/5.0 (Windows NT 6.1; WOW64) AppleWebKit\/537.36 (KHTML, like Gecko) Chrome\/52.0.2743.116 Safari\/537.36", "httpStatus": 200, "httpVersion": "HTTP\/1.1", "receivedBytes": 184, "sentBytes": 466, "clientResponseTime": 0, "timeTaken": 0.034, "WAFEvaluationTime": "0.000", "WAFMode": "Detection", "transactionId": "592d1649f75a8d480a3c4dc6a975309d", "sslEnabled": "on", "sslCipher": "ECDHE-RSA-AES256-GCM-SHA384", "sslProtocol": "TLSv1.2", "sslClientVerify": "NONE", "sslClientCertificateFingerprint": "", "sslClientCertificateIssuerName": "", "serverRouted": "52.239.221.65:443", "serverStatus": "200", "serverResponseLatency": "0.028", "originalHost": "20.110.30.194", "host": "20.110.30.194" }}

Note

Access logs with clientIP value 127.0.0.1 originate from an internal security process running on the application gateway instances. You can safely ignore these log entries.

For Application Gateway Standard and WAF SKU (v1)

ValueDescription
instanceIdApplication Gateway instance that served the request.
clientIPOriginating IP for the request.
clientPortOriginating port for the request.
httpMethodHTTP method used by the request.
requestUriURI of the received request.
RequestQueryServer-Routed: Backend pool instance that was sent the request.X-AzureApplicationGateway-LOG-ID: Correlation ID used for the request. It can be used to troubleshoot traffic issues on the backend servers. SERVER-STATUS: HTTP response code that Application Gateway received from the back end.
UserAgentUser agent from the HTTP request header.
httpStatusHTTP status code returned to the client from Application Gateway.
httpVersionHTTP version of the request.
receivedBytesSize of packet received, in bytes.
sentBytesSize of packet sent, in bytes.
timeTakenLength of time (in milliseconds) that it takes for a request to be processed and its response to be sent. This is calculated as the interval from the time when Application Gateway receives the first byte of an HTTP request to the time when the response send operation finishes. It's important to note that the Time-Taken field usually includes the time that the request and response packets are traveling over the network.
sslEnabledWhether communication to the backend pools used TLS/SSL. Valid values are on and off.
hostThe hostname with which the request has been sent to the backend server. If backend hostname is being overridden, this name will reflect that.
originalHostThe hostname with which the request was received by the Application Gateway from the client.
{ "resourceId": "/SUBSCRIPTIONS/{subscriptionId}/RESOURCEGROUPS/PEERINGTEST/PROVIDERS/MICROSOFT.NETWORK/APPLICATIONGATEWAYS/{applicationGatewayName}", "operationName": "ApplicationGatewayAccess", "time": "2017-04-26T19:27:38Z", "category": "ApplicationGatewayAccessLog", "properties": { "instanceId": "ApplicationGatewayRole_IN_0", "clientIP": "191.96.249.97", "clientPort": 46886, "httpMethod": "GET", "requestUri": "/phpmyadmin/scripts/setup.php", "requestQuery": "X-AzureApplicationGateway-CACHE-HIT=0&SERVER-ROUTED=10.4.0.4&X-AzureApplicationGateway-LOG-ID=874f1f0f-6807-41c9-b7bc-f3cfa74aa0b1&SERVER-STATUS=404", "userAgent": "-", "httpStatus": 404, "httpVersion": "HTTP/1.0", "receivedBytes": 65, "sentBytes": 553, "timeTaken": 205, "sslEnabled": "off", "host": "www.contoso.com", "originalHost": "www.contoso.com" }}

Performance log

The performance log is generated only if you have enabled it on each Application Gateway instance, as detailed in the preceding steps. The data is stored in the storage account that you specified when you enabled the logging. The performance log data is generated in 1-minute intervals. It is available only for the v1 SKU. For the v2 SKU, use Metrics for performance data. The following data is logged:

ValueDescription
instanceIdApplication Gateway instance for which performance data is being generated. For a multiple-instance application gateway, there is one row per instance.
healthyHostCountNumber of healthy hosts in the backend pool.
unHealthyHostCountNumber of unhealthy hosts in the backend pool.
requestCountNumber of requests served.
latencyAverage latency (in milliseconds) of requests from the instance to the back end that serves the requests.
failedRequestCountNumber of failed requests.
throughputAverage throughput since the last log, measured in bytes per second.
{ "resourceId": "/SUBSCRIPTIONS/{subscriptionId}/RESOURCEGROUPS/{resourceGroupName}/PROVIDERS/MICROSOFT.NETWORK/APPLICATIONGATEWAYS/{applicationGatewayName}", "operationName": "ApplicationGatewayPerformance", "time": "2016-04-09T00:00:00Z", "category": "ApplicationGatewayPerformanceLog", "properties": { "instanceId":"ApplicationGatewayRole_IN_1", "healthyHostCount":"4", "unHealthyHostCount":"0", "requestCount":"185", "latency":"0", "failedRequestCount":"0", "throughput":"119427" }}

Note

Latency is calculated from the time when the first byte of the HTTP request is received to the time when the last byte of the HTTP response is sent. It's the sum of the Application Gateway processing time plus the network cost to the back end, plus the time that the back end takes to process the request.

Firewall log

The firewall log is generated only if you have enabled it for each application gateway, as detailed in the preceding steps. This log also requires that the web application firewall is configured on an application gateway. The data is stored in the storage account that you specified when you enabled the logging. The following data is logged:

ValueDescription
instanceIdApplication Gateway instance for which firewall data is being generated. For a multiple-instance application gateway, there is one row per instance.
clientIpOriginating IP for the request.
clientPortOriginating port for the request.
requestUriURL of the received request.
ruleSetTypeRule set type. The available value is OWASP.
ruleSetVersionRule set version used. Available values are 2.2.9 and 3.0.
ruleIdRule ID of the triggering event.
messageUser-friendly message for the triggering event. More details are provided in the details section.
actionAction taken on the request. Available values are Blocked and Allowed (for custom rules), Matched (when a rule matches a part of the request), and Detected and Blocked (these are both for mandatory rules, depending on if the WAF is in detection or prevention mode).
siteSite for which the log was generated. Currently, only Global is listed because rules are global.
detailsDetails of the triggering event.
details.messageDescription of the rule.
details.dataSpecific data found in request that matched the rule.
details.fileConfiguration file that contained the rule.
details.lineLine number in the configuration file that triggered the event.
hostnameHostname or IP address of the Application Gateway.
transactionIdUnique ID for a given transaction which helps group multiple rule violations that occurred within the same request.
{ "timeStamp": "2021-10-14T22:17:11+00:00", "resourceId": "/SUBSCRIPTIONS/{subscriptionId}/RESOURCEGROUPS/{resourceGroupName}/PROVIDERS/MICROSOFT.NETWORK/APPLICATIONGATEWAYS/{applicationGatewayName}", "operationName": "ApplicationGatewayFirewall", "category": "ApplicationGatewayFirewallLog", "properties": { "instanceId": "appgw_2", "clientIp": "185.42.129.24", "clientPort": "", "requestUri": "\/", "ruleSetType": "OWASP_CRS", "ruleSetVersion": "3.0.0", "ruleId": "920350", "message": "Host header is a numeric IP address", "action": "Matched", "site": "Global", "details": { "message": "Warning. Pattern match \\\"^[\\\\d.:]+$\\\" at REQUEST_HEADERS:Host .... ", "data": "20.110.30.194:80", "file": "rules\/REQUEST-920-PROTOCOL-ENFORCEMENT.conf", "line": "791" }, "hostname": "20.110.30.194:80", "transactionId": "592d1649f75a8d480a3c4dc6a975309d", "policyId": "default", "policyScope": "Global", "policyScopeName": "Global" }}

View and analyze the activity log

You can view and analyze activity log data by using any of the following methods:

  • Azure tools: Retrieve information from the activity log through Azure PowerShell, the Azure CLI, the Azure REST API, or the Azure portal. Step-by-step instructions for each method are detailed in the Activity operations with Resource Manager article.
  • Power BI: If you don't already have a Power BI account, you can try it for free. By using the Power BI template apps, you can analyze your data.

View and analyze the access, performance, and firewall logs

Azure Monitor logs can collect the counter and event log files from your Blob storage account. It includes visualizations and powerful search capabilities to analyze your logs.

You can also connect to your storage account and retrieve the JSON log entries for access and performance logs. After you download the JSON files, you can convert them to CSV and view them in Excel, Power BI, or any other data-visualization tool.

Tip

If you're familiar with Visual Studio and basic concepts of changing values for constants and variables in C#, you can use the log converter tools available from GitHub.

Analyzing Access logs through GoAccess

We have published a Resource Manager template that installs and runs the popular GoAccess log analyzer for Application Gateway Access Logs. GoAccess provides valuable HTTP traffic statistics such as Unique Visitors, Requested Files, Hosts, Operating Systems, Browsers, HTTP Status codes and more. For more details, please see the Readme file in the Resource Manager template folder in GitHub.

Next steps

  • Visualize counter and event logs by using Azure Monitor logs.
  • Visualize your Azure activity log with Power BI blog post.
  • View and analyze Azure activity logs in Power BI and more blog post.
Backend health and diagnostic logs - Azure Application Gateway (2024)

FAQs

What should you use to see the number of past failed requests in the Application Gateway? ›

Access log: You can use this log to view Application Gateway access patterns and analyze important information. This includes the caller's IP, requested URL, response latency, return code, and bytes in and out. An access log is collected every 300 seconds.

How do you know if your backend pool members are healthy? ›

To check the health of your backend pool, you can use the Backend Health page on the Azure portal. Or, you can use Azure PowerShell, CLI, or REST API. The status retrieved by any of these methods can be any one of the following states: Healthy.

How do I check my Azure Application Gateway logs? ›

Enable logging through the Azure portal

In the Azure portal, find your resource and select Diagnostic settings. For Application Gateway, three logs are available: Access log. Performance log.

What is the default health probe of Azure Application Gateway? ›

The default probe looks only at <protocol>://127.0. 0.1:<port> to determine health status. If you need to configure the health probe to go to a custom URL or modify any other settings, you must use custom probes.

How do I find errors of failed deployments? ›

Deployment errors occur when an operation passes validation but fails during deployment.
...
To view a deployment's result:
  1. Go to the resource group.
  2. Select Settings > Deployments.
  3. Select Error details for the deployment.
  4. The error message and error code NoRegisteredProviderFound are shown.
Jan 3, 2023

How do I monitor my Application Gateway? ›

Metrics visualization

Browse to an application gateway, under Monitoring select Metrics. To view the available values, select the METRIC drop-down list. To see a current list of metrics, see Supported metrics with Azure Monitor.

What is the difference between Application Gateway and load balancer? ›

Traditional load balancers operate at the transport layer (OSI layer 4 - TCP and UDP) and route traffic based on source IP address and port, to a destination IP address and port. Application Gateway can make routing decisions based on additional attributes of an HTTP request, for example URI path or host headers.

What is the difference between gateway and load balancer? ›

An API gateway vs. load balancer comparison can be boiled down to the fact that they both manage traffic entering your website or application but have different roles. An API gateway handles authentication and security policies, while a load balancer API distributes network traffic across multiple servers.

What is backend pool in Application Gateway? ›

Backend pools

A backend pool routes request to backend servers, which serve the request. Backend pools can contain: NICs. Virtual machine scale sets.

How do I troubleshoot Azure application gateway? ›

Solution
  1. Check NSGs associated with the application gateway subnet. ...
  2. Check UDR associated with the application gateway subnet. ...
  3. Check effective NSG and route with the backend VM. ...
  4. Check presence of custom DNS in the VNet. ...
  5. If present, ensure that the DNS server can resolve the backend pool member's FQDN correctly.
Oct 20, 2022

Where are Azure diagnostic logs stored? ›

The diagnostics logs are saved in a blob container named $logs in your storage account. You can view the log data using a storage explorer like the Microsoft Azure Storage Explorer, or programmatically using the storage client library or PowerShell.

How do I check Azure DDoS logs? ›

View metrics from virtual network
  1. Sign in to the Azure portal and browse to your virtual network that has DDoS protection enabled.
  2. Under Monitoring, select Metrics.
  3. Select Add metric then select Scope.
  4. In the Select a scope menu, select the Subscription that contains the public IP address you want to log.
Feb 12, 2023

What types of diagnostic logs are available when using Azure app services? ›

Logs messages generated by your application code. The messages can be generated by the web framework you choose, or from your application code directly using the standard logging pattern of your language. Each message is assigned one of the following categories: Critical, Error, Warning, Info, Debug, and Trace.

What types of logs does Application Gateway provide? ›

For Application Gateway, three logs are available:
  • Access log.
  • Performance log.
  • Firewall log.
Nov 17, 2022

How do I check my health probe in Azure? ›

Load Balancer health probes originate from the IP address 168.63. 129.16 and must not be blocked for probes to mark your instance as up. Review probe source IP address for details. To see this probe traffic within your backend instance, review the Azure Load Balancer FAQ.

How do you check code is deployed or not? ›

Sign in with the same user that you set up in Getting started with CodeDeploy.
  1. In the navigation pane, expand Deploy, and then choose Deployments. ...
  2. To see more details for a single deployment, in Deployment history, choose the deployment ID or choose the button next to the deployment ID, and then choose View.

What are the common problems that you would face during system deployment? ›

Let us break down some common software deployment issues and their fixes.
  • Data Classification and Management. ...
  • Integration Challenges during Software Deployment. ...
  • Poor Software Deployment Process Planning. ...
  • Failing to Account for Hidden Costs. ...
  • Resistance to Change. ...
  • The Lack of a Feedback Loop.
Jun 17, 2021

How do you find error recognition? ›

Identify and mark the errors in the sentences. Think about the correct alternative for the mistake. Write the correct word instead of the error. Read the corrected sentence again to confirm it is right.

How do I check the performance of an application? ›

Below are 10 core application performance metrics that developers should track.
  1. CPU usage. CPU usage affects the responsiveness of an application. ...
  2. Memory usage. ...
  3. Requests per minute and bytes per request. ...
  4. Latency and uptime. ...
  5. Security exposure. ...
  6. User satisfaction/Apdex scores. ...
  7. Average response time. ...
  8. Error rates.
Jul 22, 2022

How to find and diagnose performance issues with Azure application Insights? ›

Select Application Insights and then select your subscription. To open the Performance panel, either select Performance under the Investigate menu or select the Server response time graph. The Performance screen shows the count and average duration of each operation for the application.

How do I monitor application performance in Azure? ›

Log in to your Azure account at https://portal.azure.com.
  1. Click Create a resource and search for “Web App + SQL”.
  2. Select the Web App + SQL option published by Microsoft.
  3. Click Create.
  4. Enter a globally unique name for the app service. ...
  5. Select the option to configure the SQL Database.
Oct 19, 2020

What are the disadvantages of Azure Application Gateway? ›

Microsoft Azure Application Gateway Cons. The graphical interface needs improvement because it is not user friendly. It takes a lot of time for a certificate to update in the system. That is a huge drawback, affecting the load-balancing side.

Do we need both API gateway and load balancer? ›

An organization's approach to managing network traffic doesn't need to use only API gateways or load balancers. Both services can function together, although they do not require each other to work.

Can API gateway replace load balancer? ›

TL;DR: yes, API Gateway can replace what a Load Balancer would usually provide, with a simpler interface and many more features on top of it.

Can we use API gateway and load balancer together? ›

To integrate your API Gateway REST API with a public Application Load Balancer, use API Gateway HTTP integration. For private Application Load Balancers, use API Gateway VPC link to first connect to a private Network Load Balancer.

What are the three types of load balancers? ›

Elastic Load Balancing supports the following types of load balancers: Application Load Balancers, and Network Load Balancers. Amazon ECS services can use these types of load balancer.

Which is better load balancing or failover? ›

From a pure availability standpoint, load balancing is, in a way, better than failover. Failover comes into play only when the main system has already failed, whereas load balancing strives to prevent failure from occurring in the first place.

What is a backend solution? ›

What is a backend solution? Backend solutions contain a set of tools and languages used in server-side programming in a web or mobile development environment.

What is backend and how it works? ›

The backend (or “server-side”) is the portion of the website you don't see. It's responsible for storing and organizing data, and ensuring everything on the client-side actually works. The backend communicates with the frontend, sending and receiving information to be displayed as a web page.

What is a backend pool in Azure? ›

The backend pool is a critical component of the load balancer. The backend pool defines the group of resources that will serve traffic for a given load-balancing rule. There are two ways of configuring a backend pool: Network Interface Card (NIC) IP address.

How do I troubleshoot my gateway? ›

Right-click on your adapter and choose “Update driver.” Select “Search automatically for updated driver software” and follow the on-screen instructions to update your drivers. After a successful update, restart your computer and check whether or not you still experience issues with the default gateway.

How do I test Azure gateway? ›

Azure portal
  1. In the Azure portal, go to your virtual network gateway.
  2. On the page for your virtual network gateway, click Connections. You can see the status of each connection.
  3. Click the name of the connection that you want to verify. In Essentials, you can view more information about your connection.
Jun 14, 2022

What is 404 in the backend server HTTP response? ›

404 Not Found: This response code occurs when the server cannot find the resources being requested by the client.

What is the difference between activity logs and diagnostic logs in Azure? ›

Of important note, the Activity Log is different from Diagnostic Logs. Activity Logs provide data about the operations on a resource from the outside (the “control plane”). Diagnostics Logs are emitted by a resource and provide information about the operation of that resource (the “data plane”).

How do I read Azure diagnostic logs? ›

Follow these steps enable logging for your Azure CDN endpoint:
  1. Sign in to the Azure portal.
  2. In the Azure portal, navigate to All resources -> your-cdn-profile.
  3. Select the CDN endpoint for which you want to enable diagnostics logs:
  4. Select Diagnostics logs in the Monitoring section:
Dec 28, 2022

What are the logs required to diagnostic Azure solution? ›

Azure Diagnostics extension sends data to Azure Storage, Azure Monitor Metrics (Windows only) and Azure Event Hubs. The Log Analytics agent collects data to Azure Monitor Logs. The Log Analytics agent is required for retired solutions, VM insights, and other services such as Microsoft Defender for Cloud.

How do I check my vulnerability in Azure portal? ›

From the Azure portal, open Defender for Cloud. From Defender for Cloud's menu, open the Recommendations page. Select the recommendation Machines should have a vulnerability assessment solution. The machine "server16-test" above, is an Azure Arc-enabled machine.

Is Azure DDoS automatically enabled? ›

It's automatically tuned to help protect your specific Azure resources in a virtual network. Protection is simple to enable on any new or existing virtual network, and it requires no application or resource changes. See Azure DDoS Protection overview for more details.

How do I test my Azure DDoS Protection? ›

Monitor and validate

Log in to https://portal.azure.com and go to your subscription. Select the Public IP address you tested the attack on. Under Monitoring, select Metrics. For Metric, select Under DDoS attack or not.

What are Azure diagnostic logs? ›

Diagnostic logs provide insights on the operations that were performed within a resource. With Microsoft Azure's diagnostic logs, you can export basic usage metrics from content delivery network (CDN) endpoints to a variety of sources. Learn more about log management with Site24x7.

What are different types of logs in Azure? ›

Types of logs in Azure
Log categoryLog type
Virtual machines and cloud servicesWindows Event Log service and Linux Syslog
Azure Storage AnalyticsStorage logging, provides metrics data for a storage account
Network security group (NSG) flow logsJSON format, shows outbound and inbound flows on a per-rule basis
5 more rows
Jan 19, 2023

What are the different types of application logs? ›

Depending on the events logged, there can be different types of application logs.
...
Access, Authentication, and Authorization Logs
  • Who logged in (and logged out)
  • Whether the operation was successful.
  • Who accessed application resources like files or database tables.
  • Who requested data.
  • How they moved across the network.

What do application logs show you? ›

Put simply, an application log is a file that contains information about events that have occurred within a software application. These events are logged out by the application and written to the file. They can include errors and warnings as well as informational events.

What is health probe in Azure Application Gateway? ›

Health probes are used to check whether one or more units in the backend pool are working correctly. The application gateway will send different requests, HTTP or HTTPS, to see if those units are working correctly, and if they are not, they will not be used for backend redirection of the client requests.

What is the difference between health check and auto heal in Azure? ›

The Health Check feature is pretty basic compared to Auto-Heal. Basically it makes a request to a predefined url and if it does not get a succesful response it will take that instance out of the load balancer pool. If it remain unhealthy it will be replaces with a new instance.

How does Azure health Check work? ›

Health check increases your application's availability by rerouting requests away from unhealthy instances, and replacing instances if they remain unhealthy. Your App Service plan should be scaled to two or more instances to fully utilize Health check.

How do you track failed requests which gets into the web application? ›

To configure Failed Request Tracing Rules using the UI
  1. Launch IIS Manager (inetmgr).
  2. Select the Default Web Site.
  3. In the Actions pane, under Configure, select Failed Request Tracing….
  4. In the Edit Web Site Failed Request Tracing Settings dialog box, check the Enable checkbox.
  5. Click OK to save changes.
Mar 22, 2022

How do I troubleshoot Azure Application Gateway? ›

Solution
  1. Check NSGs associated with the application gateway subnet. ...
  2. Check UDR associated with the application gateway subnet. ...
  3. Check effective NSG and route with the backend VM. ...
  4. Check presence of custom DNS in the VNet. ...
  5. If present, ensure that the DNS server can resolve the backend pool member's FQDN correctly.
Oct 20, 2022

Which of the following features services can you use to to monitor your live applications and automatically detect performance anomalies? ›

Smart Detection – automatic failure and anomaly detection through proactive telemetry analysis.

How an Application Gateway accepts a request? ›

How an application gateway accepts a request
  • Before a client sends a request to an application gateway, it resolves the domain name of the application gateway by using a Domain Name System (DNS) server. ...
  • The Azure DNS returns the IP address to the client, which is the frontend IP address of the application gateway.
Feb 19, 2023

How do I check HTTP error logs? ›

Location. Access and error log files are stored on individual web servers. By default on most Linux systems, you can find Apache logs at /var/log/apache , /var/log/apache2 , or /var/log/httpd . Similarly, NGINX logs are often located at /var/log/nginx by default.

How do I check IIS logs for errors? ›

Via IIS Manager, you can see a “Logging” feature. Click on this, and you can verify that your IIS logs are enabled and observe where they are being written to. You should find your logs in folders that are named by your W3SVC site ID numbers.

How do I trace IIS logs? ›

IIS log files are stored by default in the %SystemDrive%\inetpub\logs\LogFiles folder of your IIS server. The folder is configured in the Directory property on the Logging page for either the server or an individual site.

What is backend pool in application gateway? ›

Backend pools

A backend pool routes request to backend servers, which serve the request. Backend pools can contain: NICs. Virtual machine scale sets.

What are the 7 things Azure security monitor can do? ›

Use Azure Monitor to monitor these types of resources in Azure, other clouds, or on-premises:
  • Applications.
  • Virtual machines.
  • Guest operating systems.
  • Containers.
  • Databases.
  • Security events in combination with Azure Sentinel.
  • Networking events and health in combination with Network Watcher.
5 days ago

What tools or procedures would you use to diagnose troubleshoot and improve the performance of real time application? ›

To help with the process, we've provided an overview of 12 of today's top APM tools.
  1. AppDynamics APM. ...
  2. Datadog APM. ...
  3. Dynatrace. ...
  4. Instana. ...
  5. Gibraltar Software Loupe. ...
  6. ManageEngine Applications Manager. ...
  7. New Relic APM. ...
  8. Raygun APM.
Jul 21, 2022

How do I check my application Insights performance? ›

Select Application Insights and then select your subscription. To open the Performance panel, either select Performance under the Investigate menu or select the Server response time graph. The Performance screen shows the count and average duration of each operation for the application.

What are the limitations of application gateways? ›

The main disadvantage associated with application-level gateways is that they require special-purpose code for each service to be relayed, increasing the complexity and maintenance overheads.

Top Articles
Latest Posts
Recommended Articles
Article information

Author: Terrell Hackett

Last Updated:

Views: 5683

Rating: 4.1 / 5 (72 voted)

Reviews: 95% of readers found this page helpful

Author information

Name: Terrell Hackett

Birthday: 1992-03-17

Address: Suite 453 459 Gibson Squares, East Adriane, AK 71925-5692

Phone: +21811810803470

Job: Chief Representative

Hobby: Board games, Rock climbing, Ghost hunting, Origami, Kabaddi, Mushroom hunting, Gaming

Introduction: My name is Terrell Hackett, I am a gleaming, brainy, courageous, helpful, healthy, cooperative, graceful person who loves writing and wants to share my knowledge and understanding with you.