反向代理设置问题

    location /notice {
        proxy_pass http://127.0.0.1:20002/;  
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header X-real-ip $remote_addr;
        proxy_set_header X-Forwarded-For $remote_addr;
    }
    location /msg {
        proxy_pass http://127.0.0.1:20003/;  
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header X-real-ip $remote_addr;
        proxy_set_header X-Forwarded-For $remote_addr;
    }

报错了。什么情况？