Please what are the options for me in the following scenario.
We have a SQL managed instance on Azure, our client has requested that they want their data (managed instance) to sync on a weekly basis with their on premise SQL server. I suggested using Azure Data Sync but that will be costly for us and using transactional replication based on what was described here https://learn.microsoft.com/en-us/azure/azure-sql/managed-instance/replication-transactional-overview?view=azuresql is also costly as it requires that we have another managed instance to act as a broker.
Please, I'm very welcoming to ideas you may have on how to go about this.
Thank you.
Related
I have a requirement of checking whether the exact copy of master database from AWS RDS can be created in on premises or not..
I have already established the connectivity between on prem and aws. Also checked the data migration using pg dump. But i am not getting how to create the replica without using DMS. Due to some security purpose we are not supposed to use DMS. So is there any other way out to implement thi ?
Any help will be much appreciated
It appears that your goal is disaster recovery.
Amazon RDS offers a few options for this:
Amazon RDS Snapshots are a backup of the database, stored in a region. If your database is in an Availability Zone that fails, the snapshot can be restored as a new database in another AZ. All AZs are physically separate data centers, much like your own data center is physically separate from an AWS data center.
Snapshots can also be copied to other Regions, which would guarantee a separation distance between data centers.
Multi-AZ Amazon RDS Databases keep a second copy of the data in another AZ and can switch-over to the alternate AZ without losing any data. This is faster than restoring a snapshot, but costs twice as much since two separate database servers are deployed.
These options would be easier to manage than replicating your data to an on-premises system. A Multi-AZ will automatically start the secondary instance, so your app can continue operating with only a short delay and no data loss. This is much better than you could offer if you fail-over to an on-premises system.
I have a scenario as follows,
One cloud server is running an application with PGSQL as DB
Multiple local servers are running with same application with PGSQL as DB
User may access the cloud server for read/write data
User may access any of the local server to read/write data
What I need is synchronisation between all these databases. The synchronisation can be done live if connectivity is available, or immediately when connectivity is available.
Please guide me with some inputs, where can i start from.
Rethink your requirements.
Multimaster replication is full of pitfalls, and it is easy to get your databases out of sync unless you plan carefully. You'd probably be better off with a single master node.
That said, you could look at BDR by 2ndQuadrant which provides such functionality.
I m developing an application using SignalR to manage websockets and allow my clients to dialog between each other.
I m planning to host this back-office on an Azure worker role. As my SignalR requests carry data that is most of the time saved in the database, I m wondering if NoSQL's MongoDB instead of the classic SQL Server/Entity Framework couple should be a good approach.
Assuming that my application's data types will be strings for most of them, I think MongoDB will be a reliable and a performant solution, and it will allow me to get rid of Azure's SQL's database costs.
For information, the Azure worker role will be running on a machine with the following hardware: 1 core CPU, 3.5GB RAM and 50GB SSD storage.
Do you think I m on a good start with this architecture ?
Thanks
Do you think I m on a good start with this architecture?
In a word, no.
A user asked a similar question regarding running Redis on Worker Roles - Setting up Redis on Azure cloud service worker role - all of the content on that Q/A is relevant in the MongoDb context.
I'd suggest that you read my answer as it goes into more detail, but as an overview of why this is a bad architectural approach:
You cannot guarantee when a Worker Role will be restarted by the Azure Service Fabric.
In a real-world implementation of Mongo, you would run multiple nodes within a cluster, with a single Worker Role (as you have suggested in your question) this won't be possible.
You will need to manage your MongoDb installation within the Worker Role and they simply aren't designed for this.
If you are really fixed on using Mongo, I would suggest that you use a hosted solution such as MongoLabs (as suggested in earlier answers), or consider hosting it on Azure IaaS VM's.
If you are not fixed on using Mongo, I would sincerely suggest that you look at Azure DocumentDb (also suggested above), Microsoft's Azure NoSQL offering - I have used it in several production systems already and it is certainly a capable NoSQL solution; granted, it may not have all of the features available with MongoDb.
If you are looking at a NoSQL solution for caching of data (i.e. not long term storage), I would suggest you take a look at Azure Redis Cache, which is a very capable Redis offering.
Azure has its own native NoSQL Document database called DocumentDB, have you had a look at it? If I were you I would use DocumentDB unless there are some special requirements that you have that you have not mentioned, but from what little requirement info that you have posted DocumentDB would do just fine. I don't think that it is quite similar to MongoDB in terms of the basic functionality, see this article for a comparison between Azure DocumentDB and MongoDB.
I have a RDS for PostgreSQL setup in ASIA and would like to have a read copy in US.
But unfortunately just found from the official site that only RDS for MySQL has cross-region replica but not for PostgreSQL.
And I saw this page introduced other ways to migrate data in to and out of RDS for PostgreSQL.
If not buy an EC2 to install a PostgreSQL by myself in US, is there any way the synchronize data from ASIA RDS to US RDS?
It all depends on the purpose of your replication. Is it to provide a local data source and avoid network latencies ?
Assuming that your goal is to have cross-region replication, you have a couple of options.
Custom EC2 Instances
You can create your own EC2 instances and install PostgreSQL so you can customize replication behavior.
I've documented configuring master-slave replication with PostgreSQL on my blog: http://thedulinreport.com/2015/01/31/configuring-master-slave-replication-with-postgresql/
Of course, you lose some of the benefits of AWS RDS, namely automated multi-AZ redundancy, etc., and now all of a sudden you have to be responsible for maintaining your configuration. This is far from perfect.
Two-Phase Commit
Alternate option is to build replication into your application. One approach is to use a database driver that can do this, or to do your own two-phase commit. If you are using Java, some ideas are described here: JDBC - Connect Multiple Databases
Use SQS to uncouple database writes
Ok, so this one is the one I would personally prefer. For all of your database writes you should use SQS and have background writer processes that take messages off the queue.
You will need to have a writer in Asia and a writer in the US regions. To publish on SQS across regions you can utilize SNS configuration that publishes messages onto multiple queues: http://docs.aws.amazon.com/sns/latest/dg/SendMessageToSQS.html
Of course, unlike a two phase commit, this approach is subject to bugs and it is possible for your US database to get out of sync. You will need to implement a reconciliation process -- a simple one can be a pg_dump from Asian and pg_restore into US on a weekly basis to re-sync it, for instance. Another approach can do something like a Cassandra read-repair: every 10 reads out of your US database, spin up a background process to run the same query against Asian database and if they return different results you can kick off a process to replay some messages.
This approach is common, actually, and I've seen it used on Wall St.
So, pick your battle: either you create your own EC2 instances and take ownership of configuration and devops (yuck), implement a two-phase commit that guarantees consistency, or relax consistency requirements and use SQS and asynchronous writers.
This is now directly supported by RDS.
Example of creating a cross region replica using the CLI:
aws rds create-db-instance-read-replica \
--db-instance-identifier DBInstanceIdentifier \
--region us-west-2 \
--source-db-instance-identifier arn:aws:rds:us-east-1:123456789012:db:my-postgres-instance
I have read that you can replicate a Cloud SQL database to MySQL. Instead, I want to replicate from a MySQL database (that the business uses to keep inventory) to Cloud SQL so it can have up-to-date inventory levels for use on a web site.
Is it possible to replicate MySQL to Cloud SQL. If so, how do I configure that?
This is something that is not yet possible in CloudSQL.
I'm using DBSync to do it, and working fine.
http://dbconvert.com/mysql.php
The Sync version do the service that you want.
It work well with App Engine and Cloud SQL. You must authorize external conections first.
This is a rather old question, but it might be worth noting that this seems now possible by Configuring External Masters.
The high level steps are:
Create a dump of the data from the master and upload the file to a storage bucket
Create a master instance in CloudSQL
Setup a replica of that instance, using the external master IP, username and password. Also provide the dump file location
Setup additional replicas if needed
Voilà!