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azkaban 提交任务不执行直接失败

azkaban web 报错

ERROR [FlowTriggerScheduler] [Azkaban] Unable to get scheduled flow triggers 查看web下log

cat webServerLog_2020-11-27+18\:11\:24.out 

报错信息:

2020/11/30 15:38:13.483 +0800 ERROR [FlowTriggerScheduler] [Azkaban] Unable to get scheduled flow triggers
java.lang.NullPointerException
	at azkaban.flowtrigger.quartz.FlowTriggerScheduler.getScheduledFlowTriggerJobs(FlowTriggerScheduler.java:139)
	at azkaban.webapp.servlet.FlowTriggerServlet.ajaxFetchTrigger(FlowTriggerServlet.java:67)
	at azkaban.webapp.servlet.FlowTriggerServlet.handleAJAXAction(FlowTriggerServlet.java:107)
	at azkaban.webapp.servlet.FlowTriggerServlet.handleGet(FlowTriggerServlet.java:57)
	at azkaban.webapp.servlet.LoginAbstractAzkabanServlet.doGet(LoginAbstractAzkabanServlet.java:122)
	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$RequestHandler.headerComplete(HttpConnection.java:928)
	at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)
	at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
	at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
	at org.mortbay.jetty.bio.SocketConnector$Connection.run(SocketConnector.java:228)
	at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)

分析

原因是内存不足

解决

1.查看linux 内存情况

[root@localhost kafka_2.11-1.0.0]# free -h
              total        used        free      shared  buff/cache   available
Mem:           503G         25G         12G         30M        464G        475G
Swap:           29G         73M         29G

buff/cache 占用过高手动清理

[root@localhost internal]# sync
[root@localhost internal]# echo 1 > /proc/sys/vm/drop_caches
#查看清理后的内存情况
[root@localhost internal]# free -h
              total        used        free      shared  buff/cache   available
Mem:           503G         34G        467G         30M        1.8G        467G
Swap:           29G         73M         29G

参考这里手动清理centos7 buff/cache 占用过高

2.修改/bin/internal目录下internal-start-web.sh文件 第48行AZKABAN_OPTS由-Xmx3G修改为-Xmx1G

...
 47 if [[ -z "$AZKABAN_OPTS" ]]; then
 48   AZKABAN_OPTS="-Xmx1G"
...

重启azkaban问题解决

#之前先用ps命令获取web的pid，在使用kill -9 停止web进程
ps -aux|grep azkaban
kill -9 [pid]
#启动web
cd /usr/local/azkaban/azkaban-web-server
bin/start-web.sh
#重启exec
cd /usr/local/azkaban/azkaban-exec-server
bin/shutdown-exec.sh
bin/start-exec.sh