Cache issue with cms

Hi,
I am using nginx version 1.10.1 with reverse proxy function toward
Apache 2.2.15 I noticed that if I change something inside backend (eg.
modify some text on some article), that changes appear on frontend, but
I still view old post’s content into backend.
I tried to disable any caching mechanism for /wp-admin and /wp-login
I hope I did this properly, can you help me in order to figure some
errors with this configuration?

This is my nginx global config:
####################################################user nginx
nginx;worker_processes 4;
error_log /var/log/nginx/error.log;
events { worker_connections 1024;}
http { include /etc/nginx/mime.types; default_type
application/octet-stream;

Defines the cache log format, cache log location# and the main access

log location. log_format cache '***$time_local ’
'$upstream_cache_status ’ 'Cache-Control:
$upstream_http_cache_control ’ 'Expires: $upstream_http_expires ’
'$host ’ '“$request” ($status) ’ '“$http_user_agent” ’
'Args: $args ’ 'Wordpress Auth Cookie: $wordpress_auth ';
access_log /var/log/nginx/cache.log cache; access_log
/var/log/nginx/access.log;
# Proxy cache and temp configuration. proxy_cache_path
/mnt/ramdisk/nginx_cache levels=1:2
keys_zone=main:10m max_size=1g inactive=30m;
proxy_temp_path /mnt/ramdisk/nginx_temp; proxy_ignore_headers
X-Accel-Expires Expires Cache-Control Set-Cookie; proxy_hide_header
Pragma; proxy_hide_header Expires; proxy_hide_header
Cache-Control; expires 1d;

Gzip Configuration. gzip_vary off; gzip on; gzip_disable

msie6; gzip_static on; gzip_comp_level 4; gzip_proxied any;
gzip_types text/plain text/css
application/x-javascript text/xml
application/xml application/xml+rss
text/javascript;
upstream backend { ip_hash; server 127.0.0.1:8080; # IP
goes here. }

This is my nginx’s virtual host config:
server { listen xxxx.xxxx.xxx.xx:80; # IP goes here.
server_name www.domain.com; # IP could go here.

Set proxy headers for the passthrough proxy_set_header Host

$host; proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; # Let
the Set-Cookie header through. proxy_pass_header Set-Cookie;

Max upload size: make sure this matches the php.ini in .htaccess

client_max_body_size 8m;

Catch the wordpress cookies. # Must be set to blank first for

when they don’t exist. set $wordpress_auth “”; if
($http_cookie ~* “wordpress_logged_in_[^=]*=([^%]+)%7C”) {
set $wordpress_auth wordpress_logged_in_$1; }

Set the proxy cache key set $cache_key

$scheme$host$uri$is_args$args;

All media (including uploaded) is under wp-content/ so# instead of

caching the response from apache, we’re just# going to use nginx to
serve directly from there. location ~*
^/(wp-content|wp-includes)/(.*).(gif|jpg|jpeg|png|ico|bmp|js|css|pdf|doc)$
{ root /home/domain.com; }

Don’t cache these pages. location ~* ^/(wp-admin|wp-login.php){

proxy_pass http://backend; }
location / { proxy_pass http://backend;
proxy_cache main; proxy_cache_key $cache_key;
proxy_cache_valid 30m; # 200, 301 and 302 will be cached.
proxy_cache_use_stale error timeout
invalid_header http_500
http_502 http_504
http_404; # 2 rules to dedicate the no caching rule for
logged in users. proxy_cache_bypass $wordpress_auth; # Do not
cache the response. proxy_no_cache $wordpress_auth; # Do not
serve response from cache. proxy_buffers 8 2m;
proxy_buffer_size 10m; proxy_busy_buffers_size 10m; }
}}
Thank you very much