I try to use redis for http session data replication. My Use case is as follows:
We have 2 indepentent datacenters(RZ and RR) each of them has 4 tomcat servers.
I have installed redis cluster with sentinel (One Master, 2 slaves and 3 sentinels)on one dedicated server on each datacenter. Each cluster is working as expected.
Now I want to synchrinze data between the 2 Masters nodes (cross-datacenter replication), so if our loadbalancer decide to shwitch from DC RZ(Primary) to DC RR (secondary) session data is available and no session is lost.
I tried to install dynomite framework formy purpose but failling to install it. So My question can redis handle such senario without third party tools such dynomite?
Any Help to achieve the replication between datacenter is very willcome.
Sorry for my bad english.
Thank you in Advance.
No, Redis does not offer master-master solution. See redis replication and cluster tutorial to understand how redis replication works
https://redis.io/topics/replication
https://redis.io/topics/cluster-tutorial
Dynomite is brilliant active-active solution, we have been using it for quite sometime.
No, there is no normal way to do this.
Related
Can anyone explain to me what is aware client in Redis Enterprise ?
I found this post: Redis Enterprise Clustering Command Error 'CLUSTER'
I try to use Redis Enterprise Cluster with docker.
I create 3 docker redis nodes with two shards for better scalability.
So what exactly is that aware client and what is the difference between non-cluster aware ?
Also, what is regular OSS cluster ?
Thank You..
"Cluster Aware" means a Redis client that supports the OSS Cluster API (https://redis.io/topics/cluster-spec). For example, the Ruby client https://github.com/redis/redis-rb#cluster-support supports it.
A non-aware client is a client that only supports connecting to Redis in single-instance mode (and perhaps Sentinel), such as the Python client https://github.com/andymccurdy/redis-py.
The Enterprise Cluster can be used by both types of clients regardless of how the database is deployed (i.e. clustered or not).
To clear some more of the confusion:
OSS Cluster - a mode of deployment and API (i.e. not single-instance)
Enterprise Cluster - a product
We have 2 app/web servers running HA application, we need to setup redis with high availability/replication to support our app.
Considering the minimum sentinel setup requirement of 3 nodes.
We are planning to prepare the first app serve with redis master and 1 sentinel, the second app server will have the redis slave and 1 sentinel, we plan to add one additional server to hold the third sentinel node to achieve the 2 quorum sentinel setup.
Is this a valid setup ? what could be the risks ?
Thanks ,,,
Well it looks its not recommended to put the redis nodes on the app servers (where it is recommended to put the sentinel nodes there).
We ended with a setup for KeyDB (a fork from Redis) which claimed to be faster and support high availability/replication (and much more) to create two nodes within the app servers.
Of course We had to modify little in the client side to support some advance Lua scripts (There is some binary serialized data not getting replicated to the other node).
But after some effort, it worked ! as expected.
Hope this helps ...
I need an HA redis solution instead of a single instance. Should I use cluster or Sentinel? I have tried to find out the difference between them, there is no official document about this, thanks a lot.
Well, for a HA redis solution , it depends upon the number of nodes you want to configure.
According to offical Redis documentation on Redis-cluster and Redis-sentinel both provides HA Solution but.....
Redis Sentinel provides high availability for Redis. In practical terms this means that using Sentinel you can create a Redis deployment that resists without human intervention to certain kind of failures.
Redis Cluster provides a way to run a Redis installation where data is automatically sharded across multiple Redis nodes.
Redis Cluster also provides some degree of availability during partitions, that is in practical terms the ability to continue the operations when some nodes fail or are not able to communicate. However the cluster stops to operate in the event of larger failures (for example when the majority of masters are unavailable).
For more information please refer the official docs :)
Cheers
We have checked both Redis installed in Azure VM and Azure Redis Cache both are working same I can't see a difference in the performance Have anyone used both in large scale application if so can anyone share the performance and durability of both ?
Have analysed the following
Monitoring
In-zone replication
Multi-zone replication
Auto fail-over
Data persistence
Backup
Pricing
SSL Authentication & Encryption
All the above Azure redis have the upper hand
Still I want make sure which one is the best
Does using VM has any bottlenecks ?
I would go for Azure Redis Cache. Mainly because its fully managed. At the end of the day you do have nodes under the hood. But why should you care for maintaining a VM? Hotfixes? Patches, Seucirty Updates ..etc ..etc.
I would ask the question the other way around. Why should you use VMs at all?
MG
Newbie to redis here so please bear with me.
I am looking for a method to have dual datacenter in active-active configuration. My need here is that:
if a datacenter goes down the other datacenter should not need any intervention to carry on working
Networking issues, if they occur, should not prevent one or the other datacenter to fail on set/get redis calls.
Restarting failed datacenter should have a means mirror the working redis' data back before going active
I have been reading up on replication abilities of redis, what I understand is there is
master-slave(s) replication
A cluster can have masters that are sharded
But what I haven't seen is a cluster replicating to another cluster.
Question:
Is there a architecture design where all redis in one dc replicate with the other? (Looks like couchbase appears to have this)
I do see a keyspace notifier which can be used in a pub/sub, what i want to know is whether I can use it to pub/sub redis to redis from one dc to the other to act as replication.