Stream Azure Spring Apps managed component logs in real time

This article applies to: ❌ Basic/Standard ✔️ Enterprise

This article describes how to use the Azure CLI to get real-time logs of managed components for troubleshooting. You can also use diagnostics settings to analyze diagnostics data in Azure Spring Apps. For more information, see Analyze logs and metrics with diagnostics settings. For more information on streaming logs, see Stream Azure Spring Apps application console logs in real time and Stream Azure Spring Apps job logs in real time.

Prerequisites

• Azure CLI with the Azure Spring Apps extension, version 1.24.0 or higher. You can install the extension by using the following command: az extension add --name spring.

Supported managed components

The following table lists the managed components that are currently supported, along with their subcomponents:

You can use the following command to list all subcomponents:

az spring component list
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name>

Assign an Azure role

To stream logs of managed components, you must have the relevant Azure roles assigned to you. The following table lists the required roles and the operations for which these roles are granted permissions:

az role assignment create \
    --role "<Log-reader-role-for-managed-component>" \
    --scope "<service-instance-resource-id>" \
    --assignee "<your-identity>"

List all instances in a component

Use the following command to list all instances in a component:

az spring component instance list \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --component <component-name>

For example, to list all instances for flux-source-controller in ACS Gen2 version, use the following command:

az spring component instance list \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --component flux-source-controller

View tail logs

This section provides examples of using the Azure CLI to produce tail logs.

View tail logs for a specific instance

To view the tail logs for a specific instance, use the az spring component logs command with the -i/--instance argument, as shown in the next section.

View tail logs for an instance of application-configuration-service

Use the following command to view the tail logs for application-configuration-service:

az spring component logs \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --name application-configuration-service \
    --instance <instance-name>

For ACS Gen2, the command returns logs similar to the following example:

...
2023-12-18T07:09:54.020Z  INFO  16715 --- [main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8090 (https)
2023-12-18T07:09:54.116Z  INFO  16715 --- [main] org.apache.juli.logging.DirectJDKLog     : Starting service [Tomcat]
2023-12-18T07:09:54.117Z  INFO  16715 --- [main] org.apache.juli.logging.DirectJDKLog     : Starting Servlet engine: [Apache Tomcat/10.1.12]
2023-12-18T07:09:54.522Z  INFO  16715 --- [main] org.apache.juli.logging.DirectJDKLog     : Initializing Spring embedded WebApplicationContext
2023-12-18T07:09:54.524Z  INFO  16715 --- [main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 14100 ms
2023-12-18T07:09:56.920Z  INFO  16715 --- [main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8090 (https) with context path ''
2023-12-18T07:09:57.528Z  INFO  16715 --- [main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8081 (http)
2023-12-18T07:09:57.529Z  INFO  16715 --- [main] org.apache.juli.logging.DirectJDKLog     : Starting service [Tomcat]
2023-12-18T07:09:57.529Z  INFO  16715 --- [main] org.apache.juli.logging.DirectJDKLog     : Starting Servlet engine: [Apache Tomcat/10.1.12]
2023-12-18T07:09:57.629Z  INFO  16715 --- [main] org.apache.juli.logging.DirectJDKLog     : Initializing Spring embedded WebApplicationContext
2023-12-18T07:09:57.629Z  INFO  16715 --- [main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 603 ms
2023-12-18T07:09:57.824Z  INFO  16715 --- [main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8081 (http) with context path ''
2023-12-18T07:09:58.127Z  INFO  16715 --- [main] o.springframework.boot.StartupInfoLogger : Started ReconcilerApplication in 21.005 seconds (process running for 22.875)
...

View tail logs for an instance of flux-source-controller

Use the following command to view the tail logs for flux-source-controller:

az spring component logs \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --name flux-source-controller \
    --instance <instance-name>

The command returns logs similar to the following example:

...
{"level":"info","ts":"2023-12-18T07:07:54.615Z","logger":"controller-runtime.metrics","msg":"Metrics server is starting to listen","addr":":8080"}
{"level":"info","ts":"2023-12-18T07:07:54.615Z","logger":"setup","msg":"starting manager"}
{"level":"info","ts":"2023-12-18T07:07:54.615Z","msg":"Starting server","path":"/metrics","kind":"metrics","addr":"[::]:8080"}
{"level":"info","ts":"2023-12-18T07:07:54.615Z","msg":"Starting server","kind":"health probe","addr":"[::]:9440"}
{"level":"info","ts":"2023-12-18T07:07:54.817Z","logger":"runtime","msg":"attempting to acquire leader lease flux-system/source-controller-leader-election...\n"}
{"level":"info","ts":"2023-12-18T07:07:54.830Z","logger":"runtime","msg":"successfully acquired lease flux-system/source-controller-leader-election\n"}
...

View tail logs for an instance of spring-cloud-gateway

Use the following command to view the tail logs for spring-cloud-gateway:

az spring component logs \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --name spring-cloud-gateway \
    --instance <instance-name>

The command returns logs similar to the following example:

...
2023-12-11T14:13:40.310Z  INFO 1 --- [           main] i.p.s.c.g.s.SsoDeactivatedConfiguration  : SSO is deactivated, setting up default security filters
2023-12-11T14:13:40.506Z  INFO 1 --- [           main] .h.HazelcastReactiveSessionConfiguration : Configuring Hazelcast as a session management storage
2023-12-11T14:13:51.008Z  INFO 1 --- [           main] o.s.b.web.embedded.netty.NettyWebServer  : Netty started on port 8443
2023-12-11T14:13:51.810Z  INFO 1 --- [           main] o.s.b.a.e.web.EndpointLinksResolver      : Exposing 7 endpoint(s) beneath base path '/actuator'
2023-12-11T14:13:52.410Z  INFO 1 --- [           main] o.s.b.web.embedded.netty.NettyWebServer  : Netty started on port 8090
2023-12-11T14:13:52.907Z  INFO 1 --- [           main] i.p.s.c.g.r.h.HazelcastRateLimitsRemover : Removing Hazelcast map 'GLOBAL_RATE_LIMIT' with rate limit information
2023-12-11T14:13:52.912Z  INFO 1 --- [           main] i.p.s.cloud.gateway.GatewayApplication   : Started GatewayApplication in 36.084 seconds (process running for 38.651)
...

View tail logs for an instance of spring-cloud-gateway-operator

Use the following command to view the tail logs for spring-cloud-gateway-operator:

az spring component logs \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --name spring-cloud-gateway-operator \
    --instance <instance-name>

The command returns logs similar to the following example:

...
2023-12-01T08:37:05.080Z  INFO 1 --- [           main] c.v.t.s.OperatorApplication              : Starting OperatorApplication v2.0.6 using Java 17.0.7 with PID 1 (/workspace/BOOT-INF/classes started by cnb in /workspace)
2023-12-01T08:37:05.157Z  INFO 1 --- [           main] c.v.t.s.OperatorApplication              : No active profile set, falling back to 1 default profile: "default"
2023-12-01T08:37:14.379Z  INFO 1 --- [           main] o.s.b.a.e.web.EndpointLinksResolver      : Exposing 1 endpoint(s) beneath base path '/actuator'
2023-12-01T08:37:15.274Z  INFO 1 --- [           main] o.s.b.web.embedded.netty.NettyWebServer  : Netty started on port 8080
2023-12-01T08:37:15.366Z  INFO 1 --- [           main] c.v.t.s.OperatorApplication              : Started OperatorApplication in 11.489 seconds (process running for 12.467)
...

View tail logs for an instance of config-server

Use the following command to view the tail logs for config-server:

az spring component logs \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --name config-server \
    --instance <instance-name>

The command returns logs similar to the following example:

...
{"app":"config-server","ts":"2024-05-08T05:38:29.44Z","logger":"org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext","level":"INFO","class":"org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext","method":"prepareWebApplicationContext","file":"ServletWebServerApplicationContext.java","line":291,"thread":"main","message":"Root WebApplicationContext: initialization completed in 3771 ms"}
{"app":"config-server","ts":"2024-05-08T05:38:31.058Z","logger":"com.microsoft.azure.spring.service.CloudConfigServerApplication","level":"INFO","class":"org.springframework.boot.StartupInfoLogger","method":"logStarted","file":"StartupInfoLogger.java","line":57,"thread":"main","message":"Started CloudConfigServerApplication in 6.888 seconds (process running for 8.986)"}
...

View tail logs for all instances in one command

To view the tail logs for all instances, use the --all-instances argument, as shown in the following command. The instance name is the prefix of each log line. When there are multiple instances, logs are printed in batch for each instance, so logs of one instance aren't interleaved with the logs of another instance.

az spring component logs \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --name <component-name> \
    --all-instances

Stream new logs continuously

By default, az spring component logs prints only existing logs streamed to the console and then exits. If you want to stream new logs, add the -f/--follow argument.

When you use the -f/--follow option to tail instant logs, the Azure Spring Apps log streaming service sends heartbeat logs to the client every minute unless the component is writing logs constantly. Heartbeat log messages use the following format: 2023-12-18 09:12:17.745: No log from server.

Stream logs for a specific instance

Use the following command to stream logs for a specific instance:

az spring component logs \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --name <component-name> \
    --instance <instance-name> \
    --follow

Stream logs for all instances

Use the following command to stream logs for all instances:

az spring component logs \
    --resource-group <resource-group-name> \
    --service <Azure-Spring-Apps-instance-name> \
    --name <component-name> \
    --all-instances \
    --follow

When you stream logs for multiple instances in a component, the logs of one instance interleave with logs of others.

Stream logs in a virtual network injection instance

For an Azure Spring Apps instance deployed in a custom virtual network, you can access log streaming by default from a private network. For more information, see Deploy Azure Spring Apps in a virtual network

Azure Spring Apps also enables you to access real-time managed component logs from a public network.

az spring update \
    --resource-group <resource-group-name> \
    --service <service-instance-name> \
    --enable-dataplane-public-endpoint true

After you enable the log stream public endpoint, you can access the managed component logs from a public network just like you would access a normal instance.

Secure traffic to the log streaming public endpoint

Log streaming for managed components uses Azure RBAC to authenticate the connections to the components. As a result, only users who have the proper roles can access the logs.

To ensure the security of your managed components when you expose a public endpoint for them, secure the endpoint by filtering network traffic to your service with a network security group. For more information, see Tutorial: Filter network traffic with a network security group using the Azure portal. A network security group contains security rules that allow or deny inbound network traffic to, or outbound network traffic from, several types of Azure resources. For each rule, you can specify source and destination, port, and protocol.

The following table shows an example of a basic rule that we recommend. You can use commands like nslookup with the endpoint <service-name>.private.azuremicroservices.io to get the target IP address of a service.

Next steps

• Troubleshoot VMware Spring Cloud Gateway
• Use Application Configuration Service
• Stream Azure Spring Apps application console logs in real time
• Stream Azure Spring Apps job logs in real time