使用nginx搭建的文件服务器一直提示 404 Not Found ，是文件不存在还是没有权限？

使用nginx搭建一个简单的文件服务器，配置如下

user root;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;# Load dynamic modules. See /usr/share/nginx/README.dynamic.
include /usr/share/nginx/modules/*.conf;events {worker_connections 10;
}http {log_format  main  '$remote_addr - $remote_user [$time_local] "$request" ''$status $body_bytes_sent "$http_referer" ''"$http_user_agent" "$http_x_forwarded_for"';access_log  /var/log/nginx/access.log  main;sendfile            on;tcp_nopush          on;tcp_nodelay         on;keepalive_timeout   65;types_hash_max_size 2048;include             /etc/nginx/mime.types;default_type        application/octet-stream;autoindex on;               # 显示目录autoindex_exact_size on;    # 显示文件大小autoindex_localtime on;     # 显示文件时间server {listen       6000 default_server;listen       [::]:6000 default_server;server_name  _;root         /tmp/;location / {}error_page 404 /404.html;location = /40x.html {}error_page 500 502 503 504 /50x.html;location = /50x.html {}}include /etc/nginx/conf.d/*.conf;
}

配置完成后，启动nginx

service nginx restart

没有错误提示，服务正常启动，但是访问时出现了问题，
一直提示：

404 Not Found

通过观察日志发现并没有其他异常

2024/03/20 11:07:49 [error] 26641#26641: *1 "/tmp/index.html" is not found (2: No such file or directory), client: 192.168.0.0, server: _, request: "GET / HTTP/1.1", host: "192.168.0.1:6000"
2024/03/20 11:07:49 [error] 26641#26641: *1 open() "/tmp/404.html" failed (2: No such file or directory), client: 192.168.0.0, server: _, request: "GET / HTTP/1.1", host: "192.168.0.1:6000"
2024/03/20 11:07:49 [error] 26641#26641: *1 "/tmp/index.html" is not found (2: No such file or directory), client: 192.168.0.0, server: _, request: "GET / HTTP/1.1", host: "192.168.0.1:6000"
2024/03/20 11:07:49 [error] 26641#26641: *1 open() "/tmp/404.html" failed (2: No such file or directory), client: 192.168.0.0, server: _, request: "GET / HTTP/1.1", host: "192.168.0.1:6000"

各种检测和调试，发现设置目录为根目录/和其他目录正常，看来是和目录有关系，通过查看配置文件

 cat /usr/lib/systemd/system/nginx.service[Unit]
Description=The nginx HTTP and reverse proxy server
After=network-online.target remote-fs.target nss-lookup.target
Wants=network-online.target[Service]
Type=forking
PIDFile=/run/nginx.pid
# Nginx will fail to start if /run/nginx.pid already exists but has the wrong
# SELinux context. This might happen when running `nginx -t` from the cmdline.
# https://bugzilla.redhat.com/show_bug.cgi?id=1268621
ExecStartPre=/usr/bin/rm -f /run/nginx.pid
ExecStartPre=/usr/sbin/nginx -t
ExecStart=/usr/sbin/nginx
ExecReload=/usr/sbin/nginx -s reload
KillSignal=SIGQUIT
TimeoutStopSec=5
KillMode=process
PrivateTmp=true  # !!![Install]
WantedBy=multi-user.target