What are the problems in azkaban installation
Editor to share with you what are the problems in the installation of azkaban, I believe most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!
1.
This error is reported at startup.
2019-12-19 INFO [ExecutorManager] [Azkaban] Initializing executors from database.2019/12/19 ERROR [ExecutorManager] [Azkaban] No active executors found2019/12/19 ERROR [StdOutErrRedirect] [Azkaban] Exception in thread "main" 2019-12-19 ERROR [StdOutErrRedirect] [Azkaban] azkaban.executor.ExecutorManagerException: No active executors found2019/12/19 ERROR [StdOutErrRedirect] [Azkaban] at azkaban.executor.ActiveExecutors.setupExecutors (ActiveExecutors.java:52) 2019-12-19 ERROR [StdOutErrRedirect] [Azkaban] at azkaban .executor.ExecutorManager .setupExecutors (ExecutorManager.java:201) 2019-12-19 ERROR [StdOutErrRedirect] [Azkaban] at azkaban.executor.ExecutorManager.initialize (ExecutorManager.java:135) 2019-12-19 ERROR [StdOutErrRedirect] [Azkaban] at azkaban.executor.ExecutorManager.start (ExecutorManager.java:149) 2019-12-19 ERROR [StdOutErrRedirect] [Azkaban] at azkaban.webapp.AzkabanWebServer.launch (AzkabanWebServer.java:231) 2019-12-19 ERROR [StdOutErrRedirect] [Azkaban] at azkaban.webapp.AzkabanWebServer.main (AzkabanWebServer.java:224)
Solution: in the azkaban database, there is an executors table where the active of the row with port = 12321 is changed to 1. 0.
Update executors set active = 1 where port=12321
two。 After solving the above problem.
You should be able to start webserver.
But there may be an error on the page:
Problem accessing /. Reason: java.lang.NullPointerExceptionCaused by:azkaban.webapp.servlet.PageRenderException: java.lang.NullPointerException at azkaban.webapp.servlet.Page.render (Page.java:64) at azkaban.webapp.servlet.LoginAbstractAzkabanServlet.handleLogin (LoginAbstractAzkabanServlet.java:264) at azkaban.webapp.servlet.LoginAbstractAzkabanServlet.handleLogin (LoginAbstractAzkabanServlet.java:253) at azkaban.webapp.servlet.LoginAbstractAzkabanServlet.doGet (LoginAbstractAzkabanServlet.java:130) at javax.servlet.http.HttpServlet.service (HttpServlet.java:668) At javax.servlet.http.HttpServlet.service (HttpServlet.java:770) at org.mortbay.jetty.servlet.ServletHolder.handle (ServletHolder.java:511) at org.mortbay.jetty.servlet.ServletHandler.handle (ServletHandler.java:401) at org.mortbay.jetty.servlet.SessionHandler.handle (SessionHandler.java:182) at org.mortbay.jetty.handler.ContextHandler.handle (ContextHandler.java:766) at org.mortbay.jetty.handler.HandlerWrapper.handle (HandlerWrapper.java: 152) at org.mortbay.jetty.Server.handle (Server.java:326) at org.mortbay.jetty.HttpConnection.handleRequest (HttpConnection.java:542) at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete (HttpConnection.java:928)
For this NullPointerexeception
It is because the plugins/triggers directory was not found when webserver was started.
So we created an empty directory under server.
If you report this mistake.
Then delete the triggers directory in server/plugins. Then restart it.
3. This should not be a problem.
When webserver starts, an error is reported in the log. Plugins/triggers not found
Then create an empty directory server/plugins/triggers under server
Then ok.
These are all the contents of the article "what are the problems in azkaban installation?" Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!
