Is it possible to run multiple instances of the same application with a single memcached server?

Question

I'm with a problem on dockerized applications and Memcached, to store some values, apparently, when a start a new Docker instance, that runs a Spymemcached client, all the data stored in the cache are invalidate, so If I previously stored some values on cache at Node 1 and then I start Node 2, theses values are cleaned from the Memcached server, and finally if a store the same values again on Node 1 and query it on Node 2 they will be shared beyond both nodes without clean the data. Is it the expected behavior? Should I use a Memcached server for each client instance? Or is it possible to share the same Memcached server instance to multiples client without lost the stored data?

Answer 1

I migrated the Memcached client library to Folsom from Spotify and solved my problem. A curiosity about Spymencached, the problem I mentioned occurrs only when clients are running on Windows machine.

Answer 2

You can share the same memcached instance with multiple clients.

You just need to create different docker containers for Node1, Node2 and memcached.

Create them on same container network. a sample docker-compose.yml.

version: '2'
services:
   node1:
     image: <your-image>:latest
     network:
       main:
          aliases:
             - node1
  node2:
     image: <your-image>:latest
     network:
       main:
          aliases:
             - node2
  memcached:
     image: memcached:latest
     network:
       main:
          aliases:
             - memcached
network:
   main: