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Updated on 2022-12-14 GMT+08:00
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Why Cannot I Switch from the Yarn Web UI to the Spark Web UI?

Question

In FusionInsight, the Spark application is run in yarn-client mode on the client. The following error occurs during the switch from the Yarn web UI to the application web UI:

The YARN ResourceManager log shows the following information: 
2016-07-21 16:35:27,099 | INFO  | Socket Reader #1 for port 8032 | Auth successful for mapred/hadoop.<System domain name>@<System domain name> (auth:KERBEROS) | Server.java:1388
2016-07-21 16:35:27,105 | INFO  | 1526016381@qtp-1178290888-1015 | admin is accessing unchecked http://10.120.169.53:23011 which is the app master GUI of 
application_1468986660719_0045 owned by spark | WebAppProxyServlet.java:393
2016-07-21 16:36:02,843 | INFO  | Socket Reader #1 for port 8032 | Auth successful for hive/hadoop.<System domain name>@<System domain name> (auth:KERBEROS) | Server.java:1388
2016-07-21 16:36:02,851 | INFO  | Socket Reader #1 for port 8032 | Auth successful for hive/hadoop.<System domain name>@<System domain name> (auth:KERBEROS) | Server.java:1388
2016-07-21 16:36:12,163 | WARN  | 1526016381@qtp-1178290888-1015 | /proxy/application_1468986660719_0045/: java.net.ConnectException: Connection timed out | 
Slf4jLog.java:76
2016-07-21 16:37:03,918 | INFO  | Socket Reader #1 for port 8032 | Auth successful for hive/hadoop.<System domain name>@<System domain name> (auth:KERBEROS) | Server.java:1388
2016-07-21 16:37:03,926 | INFO  | Socket Reader #1 for port 8032 | Auth successful for hive/hadoop.<System domain name>@<System domain name> (auth:KERBEROS) | Server.java:1388
2016-07-21 16:37:11,956 | INFO  | AsyncDispatcher event handler | Updating application attempt appattempt_1468986660719_0045_000001 with final state: FINISHING, 
and exit status: -1000 | RMAppAttemptImpl.java:1253

Answer

On FusionInsight Manager, the IP address of the Yarn service is in the 192 network segment.

In Yarn logs, the IP address of Spark web UI read by Yarn is http://10.120.169.53:23011, which is in the 10 network segment. The IP addresses in the 192 network segment cannot communicate with those in the 10 network segment. As a result, the Spark web UI fails to be accessed.

Solution:

Log in to the client whose IP address is 10.120.169.53 and change the IP address in the /etc/hosts file to the IP address in the 192 network segment. Run the Spark application again. The Spark web UI is displayed.