SSH Troubleshooting
1) There's a connection timeout
This is a security group issue. Any timeout (not just for SSH) is related to security groups or a firewall. Ensure your security group looks like this and correctly assigned to your EC2 instance.
2) There's still a connection timeout issue
If your security group is properly configured as above, and you still have connection timeout issues, then that means a corporate firewall or a personal firewall is blocking the connection. Please use EC2 Instance Connect as described in the next lecture.
3) SSH does not work on Windows
If it says:
ssh command not found, that means you have to use PuttyFollow again the video. If things don't work, please use EC2 Instance Connect as described in the next lecture
4) There's a connection refused
This means the instance is reachable, but no SSH utility is running on the instance
Try to restart the instance
If it doesn't work, terminate the instance and create a new one. Make sure you're using Amazon Linux 2
5)
Permission denied (publickey,gssapi-keyex,gssapi-with-mic)
This means either two things:
You are using the wrong security key or not using a security key. Please look at your EC2 instance configuration to make sure you have assigned the correct key to it.
You are using the wrong user. Make sure you have started an Amazon Linux 2 EC2 instance, and make sure you're using the user ec2-user. This is something you specify when doing
ec2-user@<public-ip>(ex:ec2-user@35.180.242.162) in your SSH command or your Putty configuration
6) Nothing is working - "aaaahhhhhh"
Don't panic. Use EC2 Instance Connect from the next lecture. Make sure you started an Amazon Linux 2 and you will be able to follow along with the tutorial :)
7) I was able to connect yesterday, but today I can't
This is probably because you have stopped your EC2 instance and then started it again today. When you do so, the public IP of your EC2 instance will change. Therefore, in your command, or Putty configuration, please make sure to edit and save the new public IP.
Happy troubleshooting!
Stephane
spring boot
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/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.0.4.RELEASE)
2022-11-06 18:45:10.993 INFO 18896 --- [ restartedMain] tacos.TacoCloudApplication : Starting TacoCloudApplication on DESKTOP-UVVTDNC with PID 18896 (C:\Users\105890781\sia5-examples\spring-in-action-5-samples-master\ch01\tacos\target\classes started by 105890781 in C:\Users\105890781\sia5-examples\spring-in-action-5-samples-master\ch01\tacos)
2022-11-06 18:45:10.996 INFO 18896 --- [ restartedMain] tacos.TacoCloudApplication : No active profile set, falling back to default profiles: default
2022-11-06 18:45:11.090 INFO 18896 --- [ restartedMain] ConfigServletWebServerApplicationContext : Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@293e7ca8: startup date [Sun Nov 06 18:45:11 CST 2022]; root of context hierarchy
2022-11-06 18:45:13.133 INFO 18896 --- [ restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http)
2022-11-06 18:45:13.161 INFO 18896 --- [ restartedMain] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2022-11-06 18:45:13.162 INFO 18896 --- [ restartedMain] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat/8.5.32
2022-11-06 18:45:13.171 INFO 18896 --- [ost-startStop-1] o.a.catalina.core.AprLifecycleListener : The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: [C:\Program Files\Java\jdk1.8.0_202\jre\bin;C:\windows\Sun\Java\bin;C:\windows\system32;C:\windows;C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\windows\system32;C:\windows;C:\windows\System32\Wbem;C:\windows\System32\WindowsPowerShell\v1.0\;C:\windows\System32\OpenSSH\;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Common Files\Intel\WirelessCommon\;C:\Program Files\nodejs\;C:\Program Files\Amazon\AWSCLIV2\;C:\Program Files\PuTTY\;C:\Users\105890781\apache-maven-3.8.6-bin\apache-maven-3.8.6\bin;C:\Program Files\Java\jdk1.8.0_202\bin;C:\Users\105890781\AppData\Local\Microsoft\WindowsApps;C:\Users\105890781\AppData\Local\Programs\Microsoft VS Code\bin;C:\Users\105890781\AppData\Roaming\npm;C:\Users\105890781\apache-maven-3.8.6-bin\apache-maven-3.8.6\bin;;.]
2022-11-06 18:45:13.273 INFO 18896 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2022-11-06 18:45:13.273 INFO 18896 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 2186 ms
2022-11-06 18:45:13.372 INFO 18896 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Servlet dispatcherServlet mapped to [/]
2022-11-06 18:45:13.377 INFO 18896 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [/*]
2022-11-06 18:45:13.378 INFO 18896 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2022-11-06 18:45:13.378 INFO 18896 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2022-11-06 18:45:13.382 INFO 18896 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [/*]
2022-11-06 18:45:13.479 INFO 18896 --- [ restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2022-11-06 18:45:13.629 INFO 18896 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@293e7ca8: startup date [Sun Nov 06 18:45:11 CST 2022]; root of context hierarchy
2022-11-06 18:45:13.703 INFO 18896 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/],methods=[GET]}" onto public java.lang.String tacos.HomeController.home()
2022-11-06 18:45:13.707 INFO 18896 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.servlet.error.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2022-11-06 18:45:13.710 INFO 18896 --- [ restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.servlet.error.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2022-11-06 18:45:13.752 INFO 18896 --- [ restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2022-11-06 18:45:13.758 INFO 18896 --- [ restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2022-11-06 18:45:14.049 INFO 18896 --- [ restartedMain] o.s.b.d.a.OptionalLiveReloadServer : LiveReload server is running on port 35729
2022-11-06 18:45:14.102 INFO 18896 --- [ restartedMain] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup
2022-11-06 18:45:14.276 INFO 18896 --- [ restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path ''
2022-11-06 18:45:14.286 INFO 18896 --- [ restartedMain] tacos.TacoCloudApplication : Started TacoCloudApplication in 3.783 seconds (JVM running for 4.628)
comandos
mvn spring-boot:run
About EBS Multi-Attach
While I say that in the previous lecture that EBS volumes cannot be attached to multiple instances, I know it is not true for io1 and io2 volume types: this is called the EBS Multi-Attach feature.
From an AWS Cloud Practitioner exam perspective this out of scope for the exam.
In order to keep the course simple and accessible, I have left out this feature from the course.
If you are curious to learn about EBS Multi-Attach, you will find it in the AWS Certified Solutions Architect Associate course, or in the AWS documentation.
Happy learning!
