Maintaining a set of identical copies of the same data
Data replication is about maintaining a set of identical copies of the same data in several places, typically on different database servers.
Questions tagged [data-replication]
35 questions
9
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DVCS blessed repo replication among geographically distributed teams
My company is exploring the move from Perforce to a DVCS and we currently use lots of Perforce proxies because the software development teams are spread over Germany, China, USA and Mexico and sometimes bandwidth from one place to another is not…
dukeofgaming
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What's the difference between active-active failover and master-master replication?
As we may know, there are two main high availability patterns: fail-over and replication.
In active-active failover, both servers are managing traffic.
In master-master replication, both masters serve reads and writes and coordinate with each other…
S.D
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how to decide when to use database replication vs. custom REST applications vs. message brokers (pub / sub)
We have a distributed solution that's currently under design. There are a few points of integration where some application needs data from someone else and vice versa. We could solve by either writing REST interfaces and provide CRUD features so…
dot
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What are the theory behind implementing two mirrored HashMaps that can accept write operations? Do I need a broker to mediate conflicting writes?
So imagine two HashMaps that need to be mirrored across two different machines, A and B. Whenever I make a modification to machine A, machine B sees it and vice-versa. Problem is:
These two hash maps need to remain always identical. What computer…
Peter Mel
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In a master-slave replication mechanism, how do you avoid / cope with the fact that the master is a single point of failure? Is there a solution?
So master-slave replication is great, but it leaves the master as a single-point of failure. What is the strategy to solve this problem, if there is one?
I'm looking for the computer science theory behind it, not for a product that magically…
Peter Mel
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4
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Scalability: How does splitting a database table work on different replicated SQL Servers?
I would like to know more about the general concepts behind dividing data of a database into different servers. For example, suppose I have a SQL Server database which has a massive table. Assume one single server cannot handle the amount of data in…
Jerry Dodge
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How to reliably determine changes in a DB table since some sort of "checkpoint"?
My scenario is fairly typical, but I can't figure out a good solution. I have a DB table (in reality several unrelated tables, but let's focus on one) where there is a fair deal of activity going on. In the table:
Records are rarely…
Vilx-
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Vector clock conflict resolution in event sourced system via local timestamp - is this safe?
We have an occasionally connected, event sourced system: a budgeting application where each client can pull other client's event store from a separate storage (network share, dropbox,...).
It is our idea to assign each event the current client's…
urbanhusky
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Is there a term for data being written not being immediately available to be read?
Here is a problem I've repeatedly observed over the years:
a thread writes to something (database record, LDAP entry, etc.)
very soon afterwards, the same thread tries to read the record it just wrote
it gets back the old version of the record, not…
user168506
3
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1 answer
Filesystem superblocks and their backup copies
I'd like to understand how (modern) filesystems are implemented and having trouble to fully understand superblocks and their backups. I reference ext4 and btrfs, but the questions may also apply to other filesystems.
Ext4 stores a couple of…
grasbueschel
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MySQL setup for remote site failover
I'm designing a custom web-based inventory management and workflow system for a client of mine. One of their remote sites has fairly sketchy internet access, and needs to have no (or very little) interruption of business when their connection to the…
Dan Ray
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Can passive and active replication handle byzantine failures?
Currently studying about replication and I was wondering:
In Passive replication, we have an agreement stage where the Primary replica manager (RM) waits for ack from the backup RM, wouldn't it be possible to handle byzantine failures whereby doing…
HeeysamH
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How does client connect to replication server in oracle?
I have read couple of articles on google but not sure how DB client for example java application connect to clustered DB.
All the articles I read says client will write at master node but will use slave for read.
My question is how client will know…
user3198603
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Disaster Recovery Database Switchover options
Some info on the current setup:
We're currently using database replication - transactional replication, to be specific - between 2 servers. For sake of this post, we are replicating from a PRIMARY to a DR halfway around the globe. The goal is to…
Derreck Dean
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Notify external services about changes to data in a database (sanity check)
I'm working on a project which revolves around a database of about 750.000 entities. Let's just say these entities are musical works. Each musical work is associated with an album, one or more composers and some other entities.
The business who…
sbrattla
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