［已解决］运行gunicorn失败：[ERROR] Connection in use 127.0.0.1 8080

最近重新部署了一下应用程序，之后重新运行gunicorn，使用如下命令：

gunicorn -b 0.0.0.0:8000 manage:app --reload

之后出现了一堆错误，具体错误内容如下：

[2018-06-16 17:04:59 +0800] [24890] [INFO] Starting gunicorn 19.8.1

[2018-06-16 17:04:59 +0800] [24890] [ERROR] Connection in use: ('0.0.0.0', 8000)

[2018-06-16 17:04:59 +0800] [24890] [ERROR] Retrying in 1 second.

[2018-06-16 17:05:00 +0800] [24890] [ERROR] Connection in use: ('0.0.0.0', 8000)

[2018-06-16 17:05:00 +0800] [24890] [ERROR] Retrying in 1 second.

[2018-06-16 17:05:01 +0800] [24890] [ERROR] Connection in use: ('0.0.0.0', 8000)

[2018-06-16 17:05:01 +0800] [24890] [ERROR] Retrying in 1 second.

[2018-06-16 17:05:02 +0800] [24890] [ERROR] Connection in use: ('0.0.0.0', 8000)

[2018-06-16 17:05:02 +0800] [24890] [ERROR] Retrying in 1 second.

[2018-06-16 17:05:03 +0800] [24890] [ERROR] Connection in use: ('0.0.0.0', 8000)

[2018-06-16 17:05:03 +0800] [24890] [ERROR] Retrying in 1 second.

[2018-06-16 17:05:04 +0800] [24890] [ERROR] Can't connect to ('0.0.0.0', 8000)

一直尝试连接8000端口，这个应该是gunicorn没有关闭。

查看一下占用情况：

netstat -tulpn

可以看到如下内容：

Active Internet connections (only servers)

Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name

tcp 0 0 0.0.0.0:25672 0.0.0.0:* LISTEN 16528/beam

tcp 0 0 127.0.0.1:3306 0.0.0.0:* LISTEN 1425/mysqld

tcp 0 0 127.0.0.1:587 0.0.0.0:* LISTEN 9093/sendmail: MTA:

tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 20372/nginx -g daem

tcp 0 0 0.0.0.0:4369 0.0.0.0:* LISTEN 16621/epmd

tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1004/sshd

tcp 0 0 0.0.0.0:15672 0.0.0.0:* LISTEN 16528/beam

tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 9093/sendmail: MTA:

tcp 0 0 127.0.0.1:8000 0.0.0.0:* LISTEN 22627/python3.5

tcp 0 0 0.0.0.0:10050 0.0.0.0:* LISTEN 11530/zabbix_agentd

tcp 0 0 0.0.0.0:10051 0.0.0.0:* LISTEN 4093/zabbix_server

tcp6 0 0 :::5672 :::* LISTEN 16528/beam

tcp6 0 0 :::80 :::* LISTEN 20372/nginx -g daem

tcp6 0 0 :::4369 :::* LISTEN 16621/epmd

tcp6 0 0 :::1017 :::* LISTEN 4564/IntelliJIDEALi

tcp6 0 0 :::5050 :::* LISTEN 29792/dotnet

tcp6 0 0 :::10050 :::* LISTEN 11530/zabbix_agentd

tcp6 0 0 :::10051 :::* LISTEN 4093/zabbix_server

udp 0 0 10.104.102.216:123 0.0.0.0:* 1195/ntpd

udp 0 0 127.0.0.1:123 0.0.0.0:* 1195/ntpd

udp 0 0 0.0.0.0:123 0.0.0.0:* 1195/ntpd

udp 0 0 127.0.0.1:161 0.0.0.0:* 1239/snmpd

udp 0 0 0.0.0.0:47718 0.0.0.0:* 1239/snmpd

udp6 0 0 :::123 :::* 1195/ntpd

重点是这个内容：

tcp 0 0 0.0.0.0:10051 0.0.0.0:* LISTEN 4093/zabbix_server

PID为4093的程序占用了8000端口，直接杀掉进程，命令如下：

kill -9 4093

之后再次运行gunicorn，命令如下：

gunicorn -b 0.0.0.0:8000 manage:app --reload

已经成功运行，截图如下：

https://pdf-lib.org/Home/Details/5262