Nginx upstream绑定端口失败nginx: [emerg] bind() to 0.0.0.0:6445 failed (13: Permission denied)_nginx 启动端口绑定失败

今天在nginx配置upstream代理（四层负载均衡）重启nginx发现绑定端口失败

报错：提示端口绑定失败，权限不足

尝试将user模块改成root用户，重启nginx还是不行，并修改nginx相关目录权限为666，还是以前的报错。

[root@k8s-master2 nginx]# systemctl restart nginx
Job for nginx.service failed because the control process exited with error code. See "systemctl status nginx.service" and "journalctl -xe" for details.
[root@k8s-master2 nginx]# journalctl -u nginx
 
Dec 13 14:59:57 k8s-master2 systemd[1]: Starting The nginx HTTP and reverse proxy server...
Dec 13 14:59:57 k8s-master2 nginx[10664]: nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
Dec 13 14:59:57 k8s-master2 nginx[10664]: nginx: [emerg] bind() to 0.0.0.0:16443 failed (13: Permission denied)
Dec 13 14:59:57 k8s-master2 nginx[10664]: nginx: configuration file /etc/nginx/nginx.conf test failed
Dec 13 14:59:57 k8s-master2 systemd[1]: nginx.service: control process exited, code=exited status=1
Dec 13 14:59:57 k8s-master2 systemd[1]: Failed to start The nginx HTTP and reverse proxy server.
Dec 13 14:59:57 k8s-master2 systemd[1]: Unit nginx.service entered failed state.
Dec 13 14:59:57 k8s-master2 systemd[1]: nginx.service failed.
Dec 13 15:02:31 k8s-master2 systemd[1]: Starting The nginx HTTP and reverse proxy server...
Dec 13 15:02:31 k8s-master2 nginx[10724]: nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
Dec 13 15:02:31 k8s-master2 nginx[10724]: nginx: [emerg] bind() to 0.0.0.0:6445 failed (13: Permission denied)
Dec 13 15:02:31 k8s-master2 nginx[10724]: nginx: configuration file /etc/nginx/nginx.conf test failed
Dec 13 15:02:31 k8s-master2 systemd[1]: nginx.service: control process exited, code=exited status=1
Dec 13 15:02:31 k8s-master2 systemd[1]: Failed to start The nginx HTTP and reverse proxy server.
Dec 13 15:02:31 k8s-master2 systemd[1]: Unit nginx.service entered failed state.
Dec 13 15:02:31 k8s-master2 systemd[1]: nginx.service failed.

查看配置Nginx文件

[root@k8s-master2 nginx]# cat /etc/nginx/nginx.conf
user nginx; 
worker_processes auto;  
error_log /var/log/nginx/error.log;  
pid /run/nginx.pid;  
  
# Load dynamic modules. See /usr/share/doc/nginx/README.dynamic.  
include /usr/share/nginx/modules/*.conf;  
  
events {  
    worker_connections 1024;  
}  
stream {  
        log_format main '$remote_addr $upstream_addr - [$time_local] $status $upstream_bytes_sent';  
        access_log /var/log/nginx/k8s-access.log main;  
  
        upstream k8s-apiserver {  
                server 192.168.100.148:6443;  
                server 192.168.100.149:6443;  
                # Add more servers here if needed  
        }  
        server {  
                listen 6445; 
                proxy_pass k8s-apiserver;  
                # Add health check here if needed  
        }  
}

配置文件无误，检查系统其他配置

发现selinux没有关闭，关闭selinux，并重启nginx，nginx运行正常！

[root@k8s-master2 nginx]# setenforce 0
[root@k8s-master2 nginx]# sed -i 's/^SELINUX=permissive/SELINUX=disabled/' /etc/selinux/config
[root@k8s-master2 nginx]# systemctl restart nginx