Ошибки NGINX [alert] 1 open socket left in connection [alert] aborting

user www-data;
worker_processes auto;
pid /run/nginx.pid;

events {
worker_connections 1024;
multi_accept on;

}

http {

sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 20;
types_hash_max_size 2048;

include /etc/nginx/mime.types;
default_type application/octet-stream;

gzip on;
gzip_disable "msie6";

2018/04/07 09:27:24 [alert] 22148#22148: *9146 open socket #63 left in connection 33
2018/04/07 09:27:24 [alert] 22148#22148: *9188 open socket #55 left in connection 43
2018/04/07 09:27:24 [alert] 22148#22148: *9149 open socket #69 left in connection 60
2018/04/07 09:27:24 [alert] 22148#22148: *9147 open socket #67 left in connection 62
2018/04/07 09:27:24 [alert] 22148#22148: aborting
2018/04/07 09:39:40 [alert] 23446#23446: *849 open socket #59 left in connection 18
2018/04/07 09:39:40 [alert] 23446#23446: aborting
2018/04/07 09:39:40 [alert] 23445#23445: *950 open socket #53 left in connection 8
2018/04/07 09:39:40 [alert] 23445#23445: *949 open socket #50 left in connection 19
2018/04/07 09:39:40 [alert] 23445#23445: *954 open socket #49 left in connection 29
2018/04/07 09:39:40 [alert] 23445#23445: aborting
2018/04/07 09:48:06 [alert] 24112#24112: *498 open socket #52 left in connection 14
2018/04/07 09:48:06 [alert] 24112#24112: aborting
2018/04/07 09:48:14 [alert] 24933#24933: *9 open socket #51 left in connection 9
2018/04/07 09:48:14 [alert] 24933#24933: *10 open socket #52 left in connection 10
2018/04/07 09:48:14 [alert] 24933#24933: aborting
2018/04/07 09:48:29 [alert] 25256#25256: *4 open socket #49 left in connection 7
2018/04/07 09:48:29 [alert] 25256#25256: aborting
2018/04/07 09:53:09 [alert] 25657#25657: *342 open socket #59 left in connection 27
2018/04/07 09:53:09 [alert] 25657#25657: aborting
2018/04/07 19:11:20 [alert] 489#489: *1291 open socket #56 left in connection 16
2018/04/07 19:11:20 [alert] 488#488: *1278 open socket #64 left in connection 7
2018/04/07 19:11:20 [alert] 489#489: aborting
2018/04/07 19:11:20 [alert] 488#488: aborting