# Sync multi nginx (persistent) caching proxy for one(or more) app server **URL:** \ **Category:** NGINX\ **Created:** [August 2, 2011, 4:53am UTC](https://www.ruby-forum.com/t/sync-multi-nginx-persistent-caching-proxy-for-one-or-more-app-server/210189 "2011-08-02T04:53:24Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![dubstep](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/cdc98d/32.png) [@dubstep](https://www.ruby-forum.com/u/dubstep)\ **Post date:** [August 2, 2011, 4:53am UTC](https://www.ruby-forum.com/t/sync-multi-nginx-persistent-caching-proxy-for-one-or-more-app-server/210189/1 "2011-08-02T04:53:24Z")
Hi, I am a newbie Nginx user, so bear with me here 😉 I want to setup multiple (identical) caching proxy in front of my app server. Basically - Load balancer - multiple nginx caching proxy - app server(s) So I have two questions: 1. How do I make the cache persistent (across nginx restart)? Wiki says that keys and metadata are stored in shared memory, does that mean it’s not possible to save cache? 2. How do I sync the caches on different nginx, so that same URL request does not hit app server multiple times. Can I use something like rsync? Thanks a lot! Posted at Nginx Forum: > **[Sync multi nginx (persistent) caching proxy for one(or more) app server](https://forum.nginx.org/read.php?2,213225,213225#msg-213225)** > > Hi, I am a newbie Nginx user, so bear with me here ;-) I want to setup multiple (identical) caching proxy in front of my app server. Basically - Load balancer - multiple nginx caching proxy - app server(s) So I have two questions: ---
**Author:** ![lennydizzy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/8491ac/32.png) [@lennydizzy](https://www.ruby-forum.com/u/lennydizzy)\ **Post date:** [August 2, 2011, 5:24am UTC](https://www.ruby-forum.com/t/sync-multi-nginx-persistent-caching-proxy-for-one-or-more-app-server/210189/2 "2011-08-02T05:24:16Z")
lookup proxy\_cache\_path. Cache is stored in a folder structure then. As its filebased I persume rsync would work, although I am not sure of the exact implementation in nginx it may not be picked up by the cache loaded unless you reload. ---
**Author:** ![lennydizzy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/8491ac/32.png) [@lennydizzy](https://www.ruby-forum.com/u/lennydizzy)\ **Post date:** [August 2, 2011, 6:40am UTC](https://www.ruby-forum.com/t/sync-multi-nginx-persistent-caching-proxy-for-one-or-more-app-server/210189/3 "2011-08-02T06:40:05Z")
On Mon, Aug 01, 2011 at 10:43:53PM -0400, lennydizzy wrote: > So I have two questions: > > 1. How do I make the cache persistent (across nginx restart)? > Wiki says that keys and metadata are stored in shared memory, does that > mean it’s not possible to save cache? The cache is persistent. Keys and metadata are loaded gracefully (I hope) from disk on nginx start. > 1. How do I sync the caches on different nginx, so that same URL request > does not hit app server multiple times. > Can I use something like rsync? No, currently it’s not possible. – Igor S. ---
**Author:** ![lennydizzy](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/8491ac/32.png) [@lennydizzy](https://www.ruby-forum.com/u/lennydizzy)\ **Post date:** [August 2, 2011, 4:06pm UTC](https://www.ruby-forum.com/t/sync-multi-nginx-persistent-caching-proxy-for-one-or-more-app-server/210189/4 "2011-08-02T16:06:28Z")
On 8/1/11 10:43 PM, “lennydizzy” [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > 1. How do I sync the caches on different nginx, so that same URL request > does not hit app server multiple times. > Can I use something like rsync? You could use memc and srcache (nginx modules) to share the cache in memcache. – Brian A.