Nginx deployment nodejs binding domain name 502 has no permissions

  node.js, question

Nginx configuration:

server {
 listen 80;
 server_name  blog.caesar.com ;
 
 location ~ {
 proxy_pass http://127.0.0.1:3000;
 bracket
 
 root  /usr/local/src/microblog/;
 # access_log /home/wssgcg1213/NB/nginx.access.log;
 # error_log /home/wssgcg1213/NB/nginx.error.log;
 
 index  index.html  index.php ;
 autoindex off;
 
 location ~* .*\.(gif|jpg|jpeg|png|bmp|ico|css|js|txt|flv|swf|mid|doc|ppt|xls|pdf|txt|mp3|wma)$ {
 expires 2d;
 bracket
 
 bracket

Nginx error:

2015/07/24 01:24:45 [crit] 4584#0: *11 connect() to 127.0.0.1:3000 failed (13: Permission denied) while connecting to upstream, client: 127.0.0.1,   server:  blog.caesar.com , request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:3000/", host: "blog.caesar.com"
 2015/07/24 01:24:46 [crit] 4584#0: *11 connect() to 127.0.0.1:3000 failed (13: Permission denied) while connecting to upstream, client: 127.0.0.1,   server:  blog.caesar.com , request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:3000/", host: "blog.caesar.com"
 2015/07/24 01:24:47 [crit] 4584#0: *11 connect() to 127.0.0.1:3000 failed (13: Permission denied) while connecting to upstream, client: 127.0.0.1,   server:  blog.caesar.com , request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:3000/", host: "blog.caesar.com"
 2015/07/24 01:24:48 [crit] 4584#0: *11 connect() to 127.0.0.1:3000 failed (13: Permission denied) while connecting to upstream, client: 127.0.0.1,   server:  blog.caesar.com , request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:3000/", host: "blog.caesar.com"
 2015/07/24 01:24:50 [crit] 4584#0: *11 connect() to 127.0.0.1:3000 failed (13: Permission denied) while connecting to upstream, client: 127.0.0.1,   server:  blog.caesar.com , request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:3000/", host: "blog.caesar.com"
 2015/07/24 01:24:51 [crit] 4584#0: *11 connect() to 127.0.0.1:3000 failed (13: Permission denied) while connecting to upstream, client: 127.0.0.1,   server:  blog.caesar.com , request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:3000/", host: "blog.caesar.com"

Port access:

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Domain name access:

clipboard.png

Q help, seek superior