Redis to memcache data migration - redis

I am using redis 2.4 and i want to store all key in memcache as a backup .
I am usind Strings as redis data type and I want to store all keys with data in
memcache.

Related

Redis data is not persistent

I am new to using Redis and I am playing around a little bit with it. I have noticed that after a little time, let's say 10 minutes all the keys that I inserted just go away.
I just did the default installation showed in the documentation. I didn't configure anything with a redis.config. Is there any configuration that I need to do so my data can persist?
Environment
Redis Server
Redis server v=6.2.6 sha=00000000:0 malloc=jemalloc-5.1.0 bits=64 build=557672d61c1e18ba
Redis-cli
redis-cli 6.2.6
Ubuntu 18.08 VM.
I have also been using redisInsight to insert the keys.
there are two mechanisms for persisting the data to disk:
snapshotting
append-only file (aof)
if you want to use snapshotting, you need to add the following settings in redis.conf file
dir ./path_for_saving_snapshot
dbfilename "name_of _snapshot.rdb"
save 60 1000
with this configuration, redis will dump the data to disk every 60 seconds if at least 1,000 keys changed in that period.
if you want to use aof, you need to add the following settings in redis.conf file
appendonly yes
appendfilename "your_aof_file.aof"
appendfsync everysecond
everysecond is the default FYSNC policy. you have also other options.
You can configure your Redis instance to use either of the two mechanisms or a combination of both.

Clustered Redis 6.x dump restore to standalone redis in AWS Elasticache

We need to migrate from clustered Redis instance to no-clustered Redis instances in AWS Elasticache due to the incompatibility of certain drivers in our application but AWS does not allow creating non-clustered instances from clustered backup.
Is there any way by which we can achieve this?
I was able to save the backup in S3 and create non-clustered instance from s3 backup.

Redis DB backup and restore?

Is there any reliable backup & restore method, tool, ... for Redis DB ?
been googling around couples of hours and there was nothing just copy the dump file /var/lib/redis/dump.rdb or some scripts that uses MIGRATE (idk if this even count as backup)
Ok lets say there is Redis DB (big one) and its Windows version of Redis
github.com/MicrosoftArchive/redis
so we need a copy of this DB in other branch of company that uses final Linux version of Redis, cuz windows version is outdated and its performance is not good as Linux version.
all keys and values are encrypted and stored as binary format in Redis, so is there any reliable backup & restore for Redis DB ?
There are solutions around that helps you automate this process.
Making a Redis backup is quite simple though:
Review / update your Redis configuration.
Create a snapshot for your Redis data (known as a "dump"/"rdb file").
Save the RDB file to a remote location
To create the snapshot (2) you'll need to use redis-cli SAVEor BGSAVEcommand.
You'll then need to create a little script (you can find one here) to transfer your .rdb file to a remote storage (like AWS S3).
You can then automate all of that using CRON.
Of course, you can now use services like SimpleBackups to get all of that done for you.

How to connect correct redis node when get some data use redis command in redis cluster?

As we known, redis cluster have 16384 hash slots.when redis client connect to redis cluster, how redis client to connect real save data redis node?
The rule is quite simple, redis use CRC16(key) % 16384 to determine which slot will a key go in. If you want to do everything by yourself, you just need to calculate every key's crc16.
But generally, you don't need to do these by yourself. At the moment, almost every well-known client, like jedis, predis,StackExchange.Redis , supports the cluster mode.

Redis | Replication and common disk storage

I am just starting to use Redis for the first time. I have gone through the documentation and I came to know that Redis can be used in replication mode. But, I have some questions which are still un-answered. Let's have a quick view of use-case
I have a clustered environment of Drupal 7 code base.
There are two web servers web1 and web2 and two DB servers DB1 and DB2
DB1 and DB2 are running in master-slave mode
I have to setup Redis on both web1 and web2, web1 as master and web2 as slave
I need same backend/disk storage for both master and slave
Is it possible to setup same backend/disk storage for both master and slave?
A solution can be that I use Redis on a single server, e.g on web1. In this case requests on web2 uses Redis cache of web1. In this case I will get a delay by network. I want to avoid this situation because I want to utilize full performance of Redis i.e reading from the memory.
Is there any other workaround?
If your master Redis instance is on Web1 then all writes will have to go here. You can however read from the slave instance on Web2 locally.
http://redis.io/topics/replication