AWS RDS MySQL Cross-region replication - mysql

I need to create an RDS MySQL instance in us-east-1 and would like to replicate this data in another region (say eu-west-1). I know about read-replicas, and I will be using them also, but I wanted to have a back-up non-read-replica in another region.
Has anyone done this?
Is there code out there that does this replication?

I highly recommend switching from RDS MySQL to RDS Aurora, which is MySQL compatible. You won't have to change anything in your code, the database will still appear to be MySQL to any apps that connect to it. Among the many advantages Aurora has over MySQL is that it supports cross-region replication.

There are several ways to do this. I will cover two easy methods. RDS features are based upon engine (MySQL, Aurora, PostreSQL, etc.). Review as required.
1) Create a read-replica of your existing RDS instance in another region. Then promote that read-replica to master. Now you have a separate instance running in another region. You can then stop this instance to minimize billing (for up to seven days).
2) Create an RDS snapshot. Copy that snapshot to another region. When needed launch a new RDS instance from the snapshot.

Related

How to sync 2x AWS RDS instances

I have 2x RDS single instances (MySQL) in the same region.
The goal is to copy (A) RDS to (B) RDS on nightly basis.
Is there any way to have this configuration auto sync between 2 RDS instances?
If your goal is to copy the contents of one Amazon RDS database such that another RDS database contains identical content, then it is easiest to use a snapshot:
Create an Amazon RDS Snapshot of the source database
Launch a new Amazon RDS database instance from the Snapshot
Delete the previous Amazon RDS database 'B' database, since it is now out-of-date
The new database launched from the Snapshot will be identical to the source database (except for the instance DNS name).
This operation can be done via AWS CLI commands.
I would suggest looking into DMS ongoing replication as it seems like a potential solution for your use case https://docs.aws.amazon.com/dms/latest/userguide/CHAP_BestPractices.html#CHAP_BestPractices.OnGoingReplication
There are three approaches here.
One is that if you want to "refresh" the database schema on nightly basis, you can use logical backup by using mysqldump/mydumper to export/import the schema and put the script in the scheduler (eg. cron).
The second one you can use is snapshot backup that is provided by AWS, but you need to destroy the previous RDS instances, otherwise you will have many restored RDS from daily snapshot. Ideally, you can create some script that call AWS CLI to remove the previous RDS and restore the snapshot from daily backup. Put the script in the scheduler as well as first option.
A third option is that you can create synchronization using Amazon DMS (Data Migration Service) to migrate the data in a real-time fashion.

Daily copy of AWS Aurora database to another AWS Aurora database

We have an AWS Aurora database sitting on an instance that holds all of our production data. I want to be able to perform analytics on that data without doing it in our production environment, so I want to copy the production data on a daily basis to another AWS Aurora database on a completely different instance. Within that "analytics" database, I'll build out all the needed views and stored procedures to aggregate whatever transformed data I need to store.
At first I thought of creating an Aurora replica, but of course that's read-only. I need to find a way to do this outside of the production environment and I feel it's an easy enough task to do, but I just can't find out how to do it. Maybe I haven't been able to ask the write questions, so I came here. How can I achieve this?
This is simple AWS replication.
http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Aurora.Replication.CrossRegion.html
Also if you prefer to use mysql or any other RDBMS use
http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Aurora.Overview.Replication.MySQLReplication.html
It is similar to master slave replication with little difference in sharded data mainted in Aurora.
Replication is the correct (subjective, of course) solution, but you can't use a managed Aurora replica, which is to say you can't use an Aurora replica in the cluster.
That does not, however, mean you can't create your own asynchronous Aurora replica... which would be a second Aurora cluster, an independent master that is writable, but that uses the replication stream (the binary logs, also called "binlogs,") from the master cluster to keep its data in sync.
The one caveat: you must be extremely cautious not to write to any of the tables on the asynchronous cluster that are being replicated from the production master. Do that, of course, and replication breaks. The master cluster will be completely unaffected, but the replica cluster will stop replicating once inconsistent data is detected. But you can create additonal tables, views, and stored programs without issue.
Within an Aurora cluster, there is no need for replication in the traditional sense -- the replicas use the same backing store as the master (the "cluster volume.") Here, we're just replicating from cluster to cluster, identical to the way two ordinary MySQL servers would replicate (in one direction, only, of course).
The setup is essentially identical to the setup for replicating in and out of Aurora, to or from MySQL. Since this solution uses MySQL native replication, the steps are the same.
http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Aurora.Overview.Replication.MySQLReplication.html

Amazon RDS two way replication

I have two rds which have the same structure, each db serves one of two apps. Some of tables are using by first app some by other. I want to set up two ways read/write replication between two rds. I can do it with stand alone mysql, set table replication (https://dev.mysql.com/doc/refman/5.7/en/replication-rules-table-options.html) but can not find any option to do so for rds
This is is probably what you'd call a Really Bad Idea™.
RDS does allow you to configure an RDS instance as a slave of another machine.
http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/mysql_rds_set_external_master.html
Of course, on the same page...
Warning
Do not use mysql.rds_set_external_master to manage replication between two Amazon RDS DB instances.
...however, that appears to be because that's not how you configure an RDS instance to be a replica of another instance. When you're configuring a read-only replica, you don't use this -- RDS manages all of the replication configuration for you.
mysql.rds_set_external_master() is a stored procedure that allows you to execute CHANGE MASTER TO... since, in RDS, you lack the SUPER privilege and would otherwise be unable to do this.
The feature is designed for hot migrations from a non-RDS MySQL server to RDS, by replicating the events from the external master into RDS during the transition.
...however, if there is a way to do what you are trying to do with RDS, this would be it. Each instance would be set to use the other as its master.
The two would need to have network connectivity, which means they'd need to be in the same region and same VPC, or you'd have to handle the peering or tunnel configuration yourself to establish that network path.
This is almost certainly an unsupported configuration, but again, if there is a way to accomplish it, this would be the way. "Unsupported" doesn't mean it won't work, but only that AWS support will not likely be able to provide assistance if it doesn't.
Did I mention this might not be a good idea?

What is the difference between Database Mirroring and Database Replication such as Multi A-Z deployment in Amazon RDS?

I have an application database running with MySQL engine on Amazon RDS. For better availability of our data for users in all parts of the world I'm looking for the best solution.
In the previous version of the application, we mirrored our database in US and Singapore, so that users got a better performance in terms of speed and on our side, we had backup if any disaster occurred.
Now as we moved to Amazon, will having Multi A-Z Deployment serve us in the same way? I mean replicates the database in all regions but will RDS still work in a single region only?
I have done some studies but still not sure so please ask me any further questions if I'm being puzzling.
Thank you.
I think you need both the Multi-AZ and the Read Replica features of AWS RDS.
Multi-AZ just creates a non-accessible secondary DB in another availability zone and in case the primary fails, AWS would switch over to the secondary DB. So you have failover.
In the case you want to increase the performance, and your application can work in read-only mode in Singapore (for example), the Read Replica would be perfect. If writes are also required, you would need to route them to the primary read-write database.
AWS supports a combination of the two approaches.
RDS MySQL Multi-AZ deployments currently works only inside an Amazon EC2 region. RDS Read replica's also need to be present inside the same Amazon EC2 region. Inter region replication is the most requested feature in AWS RDS to replicate data to another RDS in Alternative Amazon EC2 region. It is in their road map currently.

Architecture of MySQL on EBS for scaling (Amazon Web Services)

I'm trying to understand how to architect an Amazon Web Services application.
I have an instance running off of EBS. As far as I understand, I need to mount the EBS drive so that I can store my MySQL database on it.
When I later want to scale up, how do I do so? I understand that I can add more server instances, but how will they be accessing the database? Since from what I understand, the EBS volume can only be attached to one server instance.
I can't speak to this particular setup as I do not have experience using EBS with a MySQL instance but how this type of scaling is typically accomplished is by dedicating a particular instance as the master database server. Any time you spin up additional web servers those are still using the master DB IP to connect. At the time in which your database is the bottleneck you then spin up a slave DB instance on one of the boxes (or its own dedicated box). You can then configure replication in either a master to slave direction or a circular replication so that you can write to the slave instance as well.
If you choose the classic master to slave replication then you will have to make sure your writes are only performed on the master DB instance.
You can setup something like Zeus or any other connection load balancer so that you only ever have to connect to a single Database IP which will then round-robin route your read connections to your pool of servers. Otherwise you'd have to manage the connections yourself which is definitely not trivial. Good luck.
Growing Amazon EBS Volume sizes
You can give a try to MySQL clustering on your EBS backed instances. I have similar query, with more requirements, posted here.
EBS Volumes capacity can be scaled up using Snapshot->launch new volume technique, alternatively storage capacity can be scaled out using EBS Striping (RAID 0).
In AWS you cannot mount same EBS Volume to 2 EC2 instances simultaneously, so when you are scaling your application you need to scale out / up your MySQL DB either thru Replication or clustering. AWS RDS is a very good option for MySQL , if your application is read intensive then you can scale out using RDS Read replica's as well. If you need write scaling then functional partition or MySQL Shards can be explored.
AWS has an entire product dedicated to this: RDS.
In all but the rarest and most specialized of circumstances you're going to be better off using RDS than trying to create and tune your own EBS/EC2/MySQL infrastructure.
RDS also directly answers your question - they directly enable the creation of readonly databases to use as query slaves. RDS also performs backups, upgrades, and all sorts of fail-over infrastructure for you.
With EBS there's no way to attach a disk to multiple EC2 instances, so you're not going to be able to build out a failure cluster using that approach. Instead you're going to need replication or backup tools of some type.