The browser cannot connect to Flink WebUI port 8081

After the author installed flink-1.15.1, start-cluster.sh started, and found that the browser could not connect to port 8081 of Flink WebUI.

Troubleshooting:

1. Win+R, enter cmd, check whether the host can ping the virtual machine, and find that the ping is successful.

Microsoft Windows [版本 10.0.19044.1889]
(c) Microsoft Corporation。保留所有权利。

C:\Users\JKing>ping 192.168.137.4

正在 Ping 192.168.137.4 具有 32 字节的数据:
来自 192.168.137.4 的回复: 字节=32 时间<1ms TTL=64
来自 192.168.137.4 的回复: 字节=32 时间<1ms TTL=64
来自 192.168.137.4 的回复: 字节=32 时间=1ms TTL=64

2. Check whether there are tasks other than flink occupying port 8081, and find that it is not occupied, because flink itself uses the port

[root@localhost ~]$ jps
12880 Jps
23859 Kafka
11902 StandaloneSessionClusterEntrypoint
24446 QuorumPeerMain
12191 TaskManagerRunner

[root@localhost ~]$ netstat -anp | grep 8081
(Not all processes could be identified, non-owned process info
 will not be shown, you would have to be root to see it all.)
tcp     0     0 ::ffff:127.0.0.1:8081      :::*     LISTEN     11902/java

3. Check whether the firewall is turned off, and found that it is not turned on

[root@localhost ~]# service iptables status
iptables：未运行防火墙。

Solution:

1. Open the flink-1.15.1/conf/flink-conf.yaml file and modify it to: rest.bind-address: 0.0.0.0 . If you deploy a cluster, remember to distribute this file

2. Restart flink

[root@localhost flink-1.15.1]# ./bin/stop-cluster.sh
[root@localhost flink-1.15.1]# ./bin/start-cluster.sh

3. The browser normally connects to port 8081 of Flink WebUI