в связи с модернизацией движка сайта нужно отвечать поисковика 200 на запрошенную старую ссылку.
вроде все просто, смотрим в доку и пишем:

error_page 404 =200 /404; # /404 - урл отдает спец страничку с кодом 200

интегрируем в конфиг:

limit_zone myzone $binary_remote_addr 10m;
proxy_cache_path /home/xxx/domains/xxx/cache/proxy levels=1:2 keys_zone=static:250m;
proxy_cache_path /home/xxx/domains/xxxx/cache/maps/jams levels=2:2 keys_zone=jams:250m inactive=15m;

server {
listen xxx:80;
server_name xxx;

limit_conn myzone 10;

access_log /var/log/nginx/domains/xxx.log combined;

charset utf-8;

set $tile_root /home/xxx/domains/xxx/cache/maps/tiles;
set $proxied_uri http://xxx;
set $xmlrpc_proxied_uri http://xxx/points;
set $editpoints_proxied_uri http://xxx/poimanager;

location ~* .*\/map\/navitms.fcgi$ {
set $fcgi_uri $uri;

if ($args ~* "^t=([0-9]{2})([0-9]{2})([0-9]{2})([0-9]{2}),([0-9]{2})([0-9]{2})([0-9]{2})([0-9]{2}),([0-9]{2})$") {
set $tile_path $1/$5/$2/$6/$3/$7/$4/$8/$9.png;
rewrite ^.*$ /map/tiles/$tile_path last;
}
if ($args ~* "^(j=[0-9]{8},[0-9]{8},[0-9]{2})(,[0-9]+)?$") {
set $args $1;
rewrite ^.*$ /map/jams/ last;
}

return 404;
}

location ~ (.*/img/poi/).*\.gif$ {
root /home/xxx/domains/xxx/html;
try_files $uri $1/1.gif =404;
}

location /navitel/theme/navitel {
root /home/xxx/domains/xxx/html/map;
}

location /map {
index manage.html;
root /home/xxx/domains/xxx/html;
}

location /map/points {
proxy_cache off;
proxy_pass $xmlrpc_proxied_uri?$args;
}

location /map/poimanager {
proxy_cache off;
proxy_pass $editpoints_proxied_uri?$args;
}

location @proxy_tiles {
proxy_pass $proxied_uri$request_uri;
proxy_store_access user:rw group:rw;
proxy_store $tile_root/$tile_path;
}

location ^~ /map/tiles/ {
internal;
alias $tile_root/;
if_modified_since before;
try_files $uri @proxy_tiles;
}

location = /map/jams/ {
internal;
proxy_cache_valid 200 302 5m;
proxy_cache jams;
proxy_pass $proxied_uri$fcgi_uri?$args;
}

location / {
proxy_pass http://localhost:8080;
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
client_max_body_size 500m;
# error_page 404 = /404; # все равно выдает 404 код
}

location ^~ /media {
root /home/xxx/data/app/src/main/webapp;
access_log off;
expires 43200s;
}

location ^~ /media/resources {
rewrite /media/resources/(.*)$ /$1 break;
root /home/xxx/data/files/resources;
access_log off;
expires 43200s;
}

location ^~ /media/video {
rewrite /media/video/(.*)$ /$1 break;
mp4;
limit_rate 200k;
root /home/xxx/data/files/video/encoded;
}

location ^~ /mp4 {
mp4;
root /home/xxx/data/files/video;
}

location ^~ /media/images/uploaded {
rewrite /media/images/uploaded/(.*)$ /$1 break;
root /home/xxx/data/files/images/uploaded;
access_log off;
expires 43200s;
}
location ^~ /media/images/original {
rewrite /media/images/original/(.*)$ /$1 break;
root /home/xxx/data/files/images/original;
access_log off;
expires 43200s;
}

location ^~ /internal/attachment {
mp4;
rewrite /internal/attachment/(.*)$ /$1 break;
root /home/xxx/data/files/attachment;
access_log off;
expires 43200s;
}

error_page 404 = /404; # все равно выдает 404 код
error_page 501 502 503 504 505 /media/html/; # хотя 503 ошибку отрабатывает
}

Че забыл, что пропустил, куда копать?