Fastcgi retry upstream (transparent php-fpm restart)?


I’m using nginx with 1 php-fpm (via unix socket), and i’m wondering if
there is a way to make nginx retry on error, something like
fastcgi_next_upstream but for the same upstream.

I would like to be able to transparently restart php-fpm and not send
502 to the clients

So, is there a way to make nginx retry the same upstream for X seconds
retry every Y seconds for max Z attempts or …) (on errors like
failed (111: Connection refused) while connecting to upstream”) ?

I’m open to any tricks

Thanks in advance

p.s: I already know about atomic/transparent php deployment with
“$realpath_root” and multiple docroot (