Multi region EC2 & RDS replication from Region A to various other regions - amazon-web-services

Our current server consisting of an 2x EC2 instances and RDS (Read/Write) database is in Mumbai Region. However I would like to copy everything (2x EC2 & RDS (R/W)) across to Sydney, and other to other regions.
Ideally I would like to replicate the contents in those instances as well.
Does anyone know a quick and easy way of doing this?
Edit 25/01/2019:
However I would like to copy everything including what ever is inside the instances (2x EC2s and the RDSs)
Edit 29/01/2019:
The purpose is to "scale/expand out". I want to have the same infrastructure replicated 1-to-1 (exactly/identically) across various regions.

It is simple!
- For EC2 - you need to create an AMI of those instances then right click on the AMI you've just created and choose "copy AMI" to the designated region.
For RDS
If you just wanna copy data to another region then take a snapshot then copy that snapshot to destination region
If you want to make the RDS replicate to another region continuously then you need to create a read-replica from your RDS instance.

Option for replicating environment depends on how much downtime can you tolerate.
If you are okay with downtime
1. Copy the AMI of EC2 instance and snapshot of RDS to another regions
2. Bring up your new environment.
This is perfect for non critial workload
If this is critical application
1. Copy the AMI of ec2 instance ( I am assuming this would be your web/app instnaces) For real time replication use rsync or robocopy .. or solution like cloudendure .
2. Create a new RDS instance in sydney
3. USE DMS migration tool .. create source and target relationship
4. once insync cut off the relation bring new environment in sydney

As suggested by previous answers for EC2 you can create AMIs and then move the AMI to a different region.
For RDS, you can either create read replicas (and read replicas of read replicas, but beware of latency), read replicas are used to mainly improve read performance of your app.
You can also create a Multi AZ backup which will act as a disaster recovery site. However, note that Multi-AZ is only used in case of a failover. Moreover, Multi-AZ involves Synchronous data copy and read replicas are asynchronous, so read replicas can demonstrate eventual consistency behavior.
But the real question here is - What are you trying to achieve?
Are you trying to "scale out" your infrastructure to support huge traffic to your application? Or are you simply trying to setup disaster recovery (DR)?
If your answer is DR, then the approach is pretty straight forward with Multi AZ and EC2 instance snapshots. But if the answer is scaling out and performance, you really need to be thinking of better strategies such as using Cloudfront (CDN) if it is a web app, using Elasticache in-memory cache for frequently read data, or RDS read replicas, using Elastic Load Balancers with Dynamic/Step scale-out/scale-in. Other, methods would be to evaluate the type of RDS storage subsystem used i.e. using Provisional IOPs vs. Using General Purpose SSD, checking if there are any NAT “instance” bottlenecks in your VPC and so on.
It may be tempting to spin up all these redundant copies of EC2 AMIs or RDS read replicas with a click of a button, but you really need to be thinking about the cost you are going to incur on a monthly basis for completely un-used resources.

Related

How to setup AWS RDS standalone instance without traffic from actual RDS cluster

We need to know what are the best options to set AWS RDS instance (Aurora mysql) that is standalone and does not get traffic from actual RDS cluster.
Requirement is for our data team to write analytical queries but we do not want it to impact actual application and DB performance. Hence we need a DB which always has near to live data but live traffic or application does not connect to this instance.
Need to know which fits better, DL clone OR AWS Pilot light OR AWS Warn standby OR AWS hot standby OR
multi-AZ configuration.
Kindly let us know which one would fit our requirement better.
We have so far read about below 3 options,
AWS Amazon Aurora DB clone, https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/Aurora.Managing.Clone.html
AWS Pilot light or AWS Warn standby or AWS hot standby
. https://aws.amazon.com/blogs/architecture/disaster-recovery-dr-architecture-on-aws-part-iii-pilot- light-and-warm-standby/
With multi-AZ configuration, we can create a new instance in new AZ, so that his instance will have a different host (kind off, a fail over strategy), where traffic to his instance will be from our queries and not from live prod application, unless there is some fail over issue.
Option 1, Aurora cloning says
Run workload-intensive operations, such as exporting data or running analytical queries on the clone.
...which seems to be your use case here.
Just be aware that the clone will not see any changes to the original data after it is made. So you will need to periodically delete and re-clone to get the updated data
Regarding option 2, I wrote those blog posts, and I do not think that approach suits your use case. That approach is for disaster recovery
Option 3 may work. To modify it a bit, the concept here is to create an Aurora Replica, which as you say is a separate instance. The problem here is the reader endpoint for your production workload, it may hit that instance (which is not what you want)
EDIT: Adding new option 4
Option 4. Check out Amazon Aurora zero-ETL integration with Amazon Redshift. This zero-ETL integration also enables you to analyze data from multiple Aurora database clusters in an Amazon Redshift cluster.

What is the best way to automatically auto scale AWS RDS?

I want to autoscale AWS RDS automatically with scripts based on the metric monitoring.
RDS doesn't really do this for Read-Write
Multi AZ Write-Read database copies are intended for failover from primary to secondary if there is an availability problem. They don't address the problem of performance
Read replicas can be used to increase performance but they are read only
It might be possible to look at a load metric and use a Cloudwatch alarm to start an extra read replica. Read replicas can be used via an ELB or NLB
But probably this isn't a good idea. While an existing RDS is making a read replica, performance is degraded. RDS read replicas are quite slow to come up and become available so it's unlikely to respond in a good way to transient demand
You can make an API call to Modify an RDS Instance, including changing the instance class.
Amazon RDS will provision a new instance of the desired class and will then re-point the Endpoint to the new instance. Existing connections will be terminated, but applications can reconnect and all the data will be there.
Rather than scaling the RDS instance, you could always consider a caching layer, such as Amazon ElastiCache that supports Redis and Memcached. Most applications are read-heavy, which is ideal for using a cache. This can significantly improve application performance without having to scale the database.
In simple, it can be possible with Aurora 5.7 DB RDS instances only, they provide an option to auto-scale based on cloud watch metric conditions i.e CPU utilization etc.

How are Amazon RDS Database Instances Provisioned?

I've been considering moving some databases from self-hosted database instances (e.g. MySQL or PostgreSQL on Linux, either bare-metal or within AWS itself) into Amazon RDS, but it's unclear to me how everything will behave once I've created the database and it's time for maintenance to begin.
For example, I have to choose the type of instance(s) that will be used for the database, which I guess means how responsive everything will be, and there is an option for multi-AZ deployments, but it's not clear how many of those types of instances I'm actually configuring. (Presumably, multi-AZ deployment requires at least two instances).
There are options for Failover, which leads me to believe that I can rely on the service to stay up if there are problems with an instance, but then there is also a section for selecting maintenance windows for automated upgrades, which I find confusing. If I were administering e.g. a two-instance MySQL setup, I'd upgrade one instance and then the other to avoid any downtime. Is that not how RDS behaves?
RDS advertises support for automatic "minor version upgrades" (yes, please), but doesn't say anything about OS upgrades. Presumably, the db engine will be running on Amazon Linux or something similar, and will periodically require updates to those packages. Does that all happen automatically, or do I need to manually perform those upgrades, etc.?
The whole point of using something like RDS is that the service should become something I no longer have to worry about: I don't have to deal with package maintenance, upgrades, failover, or unexpected downtime (as long as I pay enough, of course). But all of the options for the RDS instance are making me skeptical of the advantages provided by RDS over just running everything myself.
Can anyone with experience with AWS RDS comment on their experiences with maintenance, upgrades, and failover?
These were the same concerns which we had when we were planning to use RDS. Now that we are effectively using AWS RDS for multiple production workloads, let me try to clarify your queries. Hope this helps.
Your Question 1 : I have to choose the type of instance(s) that will be used for the database, which I guess means how responsive everything will be
Answer : Yes. This is to define what capacity (CPU,RAM etc) you will need for your database workload
Your Question 2 : There is an option for multi-AZ deployments, but it's not clear how many of those types of instances I'm actually configuring.
Answer : Multi-AZ deployments are to ensure high availability. AZ (Availability Zones) are isolated locations within an AWS Region to provide better protection against disaster scenarios. So when we choose a Multi AZ deployment, RDS will place 2 instances of your database server in 2 Availability Zones in the region where you are provisioning.
This is done automatically by RDS and we dont have to setup/maintain 2 servers separately/manually. ( Note : Your VPC should have atleast 1 subnet in each of the 2 different AZ to provision Multi AZ Setup)
Your Question 3: If I were administering e.g. a two-instance MySQL setup, I'd upgrade one instance and then the other to avoid any downtime. Is that not how RDS behaves?
Yes. RDS does it by itself without manual intervention if you enable Automatic Upgrades while setting up RDS (Only if you choose to have Multi AZ option)
Your Question 4 : RDS advertises support for automatic "minor version upgrades" (yes, please), but doesn't say anything about OS upgrades.
Answer : RDS dont expose/provide any OS access to us. The underlying OS and its upgrades/other activities are all done without affecting the RDS services hosted on top of it. We dont have to do anything about the OS of RDS. So we can forget about that part.
Your question 5 : Regarding Failover of AWS RDS Multi AZ database
I would classify into 2 cases.
Case 1 : Fail-overs required during maintenance/other automatic activities done by Multi AZ RDS instance.
Here, RDS will automatically do the failover one instance at a time. It will first move all the ongoing traffic to second instance and then upgrade/reboot the first instance and then do the same with second instance.
Case 2 : Fail-overs required during manual reboot/manually triggered actions done on Multi AZ RDS instance.
In this case, during the reboot, AWS RDS provides an option for you to select whether the reboot should be with failover or without one.

Migrate Aurora DB from one VPC to another

We have 4 standalone, non-multiAZ aurora DB instances in a VPC and we want to move them to aurora instances in another VPC.
As I understand there are 3 ways to migrate DB instances:
1) Modify the DB instance's Subnet group to change the VPC.
However this is not supported for Aurora instances yet.
2) Create a read replica, and when slave catches up, stop the slave and take it's snapshot to create a DB instance in the different VPC and use external slave then to again resume the replication.
I have a few question around this second method. As Aurora is using some different
replication method, the result of show slave status; command is empty.
Also by default the binlog_format is OFF so not sure if I have to modify it and
then restart the instance to take note of the binlog etc.
Have anyone done this before and can guide me? I don't want to restart the instance
to later find out that it is not working, as it is a very critical DB and I want to
minimize the downtime.
3) Use Amazon DMS service, however I cannot find the source DB details for Aurora in the documentation here.
I need to find out what all permissions to give to the replication user
I'll create for this. This command in aurora is not working,
GRANT REPLICATION CLIENT, REPLICATION SLAVE ON . TO 'replication_user'#'%'
IDENTIFIED BY 'aaaaaa';
Any help would be appreciated.
You should be able to restore from a snapshot. I migrated aurora across VPCs using this approach. I hoped we could create a read-replica in a different VPC but at the moment I think you can only create one in a different region.
One strange side effect I have found and i'm not sure why this happens is that in the orginal cluster multi-az was 2 Zones and in the restored cluster multi-az is No. This hasn't affected things that I can see. I still have a cluster with writer and reader
Create a snapshot and restore it to a new cluster. When you do that, use a new subnet group created for the second VPC. That's the best way to achieve this. Like you called out, you cannot change subnet group for an existing cluster.
In your approach #2, you mention having to create a slave and then taking a snapshot. That's not required. All instances in a cluster are connected to the same shared volume, so you can just go ahead and create a snapshot from your single instance cluster directly. Just make a note that snapshots are a cluster level action, and not an instance level action in Aurora.
From https://aws.amazon.com/premiumsupport/knowledge-center/rds-vpc-aurora-cluster/
It states that
Create a clone in a different VPC
If you clone a database in an Aurora cluster, you can change the VPC of the clone. > However, the subnets in the VPC must map to the same set of Availability Zones. For more information, see Cloning Databases in an Aurora DB Cluster.
It does work though can't see a way via the console to break the replication. We are using this as a faster way of migrating than snapshot and restore. Stopping the original master would break replication but though you could do it cleaner

AWS - HA NFS - Best practices

Anyone have a sound strategy for implementing NFS on AWS in such a way that it's not a SPoF (single point of failure), or at the very least, be able to recover quickly if an instance crashes?
I've read this SO post, relating to the ability to share files with multiple EC2 instances, but it doesn't answer the question of how to ensure HA with NFS on AWS, just that NFS can be used.
A lot of online assets are saying that AWS EFS is available, but it is still in preview mode and only available in the Oregon region, our primary VPC is located in N. Cali., so can't use this option.
Other online assets are saying that GlusterFS is a way to go, but after some research I just don't feel comfortable implementing this solution due to race conditions and performance concerns.
Another options is SoftNAS but I want to avoid bringing in an unknown AMI into a tightly controlled, homogeneous environment.
Which leaves NFS. NFS is what we use in our dev environment and works fine, but it's dev, so if it crashes we go get a couple beers while systems fixes the problem, but on production, this is obviously a no go.
The best solution I can come up with at this point is to create an EBS and two EC2 instances. Both instances will be updated as normal (via puppet) to maintain stack alignment (kernel, nfs libs etc), but only one instance will mount the EBS. We set up a monitor on the active NFS instance, and if it goes down, we are notified and we manually detach and attach to the backup EC2 instance. I'm thinking we also create a network interface that can also be de/re-attached so we only need to maintain a single IP in DNS.
Although I suppose we could do this automatically with keepalived, and a IAM policy that will allow the automatic detachment/re-attachment.
--UPDATE--
It looks like EBS volumes are tied to specific availability zones, so re-attaching to an instance in another AZ is impossible. The only other option I can think of is:
Create EC2 in each AZ, in public subnet (each have EIP)
Create route 53 healthcheck for TCP:2049
Create route 53 failover policies for nfs-1 (AZ1) and nfs-2 (AZ2)
The only question here is, what's the best way to keep the two NFS servers in-sync? Just cron an rsync script between them?
Or is there a best practice that I am completely missing?
There are a few options to build a highly available NFS server. Though I prefer using EFS or GlusterFS because all these solutions have their downsides.
a) DRBD
It is possible to synchronize volumes with the help of DRBD. This allows you to mirror your data. Use two EC2 instances in different availability zones for high availability. Downside: configuration and operation is complex.
b) EBS Snapshots
If a RPO of more than 30 minutes is reasonable you can use periodic EBS snapshots to be able to recover from an outage in another availability zone. This can be achieved with an Auto Scaling Group running a single EC2 instance, a user-data script and a cronjob for periodic EBS snapshots. Downside: RPO > 30 min.
c) S3 Synchronisation
It is possible to synchronize the state of an EC2 instance acting as NFS server to S3. The standby server uses S3 to stay up to date. Downside: S3 sync of lots of small files will take too long.
I recommend watching this talk from AWS re:Invent: https://youtu.be/xbuiIwEOCAs
AWS has reviewed and approved a number of SoftNAS AMIs, which are available on AWS Marketplace. The jointly published SoftNAS Architecture on AWS White Paper provides more details:
Security (pages 4-11)
HA across AZs (pages 13-14)
You can also try a 30 day free trial to see if it meets your needs.
http://softnas.com/tryaws
Full disclosure: I work for SoftNAS.