No two processes can guarantee data consistency unless using shared memory with some kind of locking on update. And given two servers don't share memory, two processes running on these servers can not guarantee consistency either.
To put the simple terms...
App writes to node-A, node-A (/process on node-A) crashes before change is synced from node-A to node-B, data is lost.
This is true for redis and true for postgresql/ mysql or any similar database. Difference between redis and a "database" is that database protects against this problem by writing change to durable storage before telling app that write is successful. Redis
To put the simple terms... App writes to node-A, node-A (/process on node-A) crashes before change is synced from node-A to node-B, data is lost.
This is true for redis and true for postgresql/ mysql or any similar database. Difference between redis and a "database" is that database protects against this problem by writing change to durable storage before telling app that write is successful. Redis
So if one wants to have a consistent session storage, one should use a proper database or use AOF redis persistense with single node (https://chatgpt.com/s/t_6a24ab818e2881918db959cec8d8cc2d)