Questions tagged [failover]
Failover is the concept of moving services from one host or node to another in order to provide high availability in a computing system.
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Clustering vs. transactional replication vs. availability groups
Assuming you need to make sure your application that relies on SQL Server 2012 as its database backend is available around the clock, even if one server machine fails.
As a developer and not a DBA, I ...
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Automating failover in PostgreSQL 9.1
How does one setup two identical servers for automatic failover in PostgreSQL 9.1.
OS
Centos 5
PostgreSQL 9.1 compiled from source
The postgres user account exists on both machines and has a ...
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PostgreSQL failover and replication
I'm evaluating PostgreSQL 9.1 and have few questions related to failover and replication details.
I have few test scenarios. First one with a Master server and few Slaves. In case Master crashes I ...
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If I fail over one database, do the others that share the same mirror endpoint fail over as well?
We have two databases setup for mirroring on a single SQL Server instance: a test database and a production database. Both get mirrored to another server using the exact same endpoints.
If I go into ...
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What are the differences between Mirroring and Failover Clustering and when is each one recommended over the other?
What are the main differences between Mirroring and Failover Clustering?
What kind of problem each one solves and in what kind of scenarios is each one recommended over the other?
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Always On Failover Clustering vs Always On Availability Groups
I have some concerns over my understanding of SQL Server Always On. Kindly can you correct me (conceptually) where needed:
Always On Clustering and Always On Availability Groups are 2 separate ...
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PostgreSQL Failover - What tools should I use?
Here is the scenario:
There are two machines running CentOS 6.2 - machine0 and machine1
Both have PostgreSQL 9.1 installed.
One of them should be active, as a master system and through asynchronous ...
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Is "AlwaysOn" not always "Always On?"
We created a Windows Failover Cluster, then added two instances of SQL Server as nodes of a SQL Server failover cluster.
We set the servers to use "AlwaysOn Availability Groups" in SQL Configuration ...
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Why is there automatic failover for HA and manual failover for DR?
I am reading this summary from the book 'Pro SQL Server 2019 Administration' from Carter:
And it specifies:
hot → automatic failover → used for high availability (HA)
warm → manual failover → used ...
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2
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How to Configure PostgreSQL Hotstandby Automatic Failover
I have configured two PostgreSQL servers to have hot standby by streaming.
How can I configure it so that when the master server goes down, the slave server will become the new master automatically?
user2597012
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Does a replica set with only two machines make sense?
A lot of MongoDB tutorials, when they talk about replica sets, give examples of two machines: one originally initialized as primary, and another one originally created as secondary.
As I understand ...
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Can we use old primary to sync with standby after failover in PostgreSQL?
If my standby (postgres) is behind by few seconds before failover. What is the easiest way to sync back my old primary after failover in PostgreSQL.
In Oracle we have the option of Reinstating a ...
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7
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1
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Failover timeout problem
I'm looking for an additional bit of help with regard to some problems I'm looking at for one of my company's clients. Basically I have two related problems with regard to a 2-node active/active ...
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How do I configure AWS Aurora to separate write/read operations
I want to migrate my database instance from AWS RDS MySQL to Aurora, but I have a doubt about replication and how Aurora management the write/read operations.
I have my application and I want to ...
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3
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Understanding two NICs requirement for SQL fail over cluster
I am trying to make an SQL Server 2012 failover cluster. I have two DB machines. I understand that both machines need 2 NICs each. In my organization the IP scheme assigned is something like 192.168.1....
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Availability Group - how much data was lost after forced failover
Let's consider a SQL Server AlwaysOn cluster with two nodes in asynchronous replication.
Is there any way to calculate how much data was lost after forced failover?
I mean in terms of time, to be able ...
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Restart the active node services without failover
On a 2 node Windows Server Failover cluster configuration, how do I restart the SQL Server services without failing over to the other node?
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Is MSDTC required for SQL Server 2012 Fail Over Cluster?
I am making a 2 node SQL Server 2012 Failover Cluster; do I need to install the MSDTC component?
If yes, can both be installed on single shared disk?
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2
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Force a Member to Become Primary in mongodb
I looked into answers but nothing works for me in mongo 2.6.11 cluster 'nms' (members nms01m and nms02) below. I want my current secondary nms01m to become primary, and now nms02 is primary instead of ...
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InnoDB Master-Master replication goes inconsistant after power failure tests
Afternoon gents,
I'm currently stress testing a Master-Master replication setup using InnoDB as database engine.
We're using this simple script for testing which we run in Linux CLI from a remote ...
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1
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What is actually happening when postgresql discovers the trigger file and promotes it self from slave to master?
I have a streaming replication setup between two postgres servers (master: server A, slave: server B). I'm wondering what's actually happening under the hood when I touch the trigger file and the ...
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1
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The definition of object '[sp_name]' has changed since it was compiled on fail-over to mirror database
We have two SQL 2012 database servers configured in a mirror with a witness for automatic fail-over.
Yesterday the primary server suffered a HDD degradation which triggered the fail-over, however ...
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Always On AG is Down when service is stopped
I have SQL Server 2014 running on Windows Server 2012 R2.
There are three nodes, one is remote DataCenter. So two nodes have voting.
Failover Cluster is using file share witness on remote server.
If ...
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1
answer
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Failover scenario with principal "hard down"
My company has a failover pair of SQL Server 2005 instances, which provide database availability for a UL-licensed alarm/call center, where uptime and availability are critical for life safety.
Here'...
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2
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MySQL InnoDB over a Raw Device in an Active/Passive topology
We have an Active/Passive topology where there are two x86 complexes with a shared raw storage, where only one of the nodes in a given moment has an access to the shared storage (AKA the active node). ...
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1
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Database as a service (DbaaS) over dimensions--performance, scalability, & reliability?
MySql Database as a service:
Amazon
Xeround
Another eg. PostgreSQL Database-as-a-Service.
You can get the list of similar products here.
Does anyone have details on their performance, reliability, ...
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Understanding of SQL Server active/active cluster
I have a vague understanding of SQL Server's active/active cluster. Can anyone help to confirm if my understanding is correct?
As I understand, active/active cluster use two or more Windows servers. ...
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Postgres 9.4, replication slots, doesn't work failover master
I've installed postgres master and slave nodes by this manual:
At the master (10.0.0.1):
sudo -u postgres initdb -D /data/postgres/main
Change postgresql.conf:
listen_addresses = '*'
wal_level = ...
5
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1
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SQL Server ODBC Mirror/Failover Partner
Background/Context
We are in the process of moving our SQL Server 2000 databases to a mirrored SQL Server 2008 R2 server with a witness and automatic failover. We have both .Net and Access ...
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2
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Improve AlwaysOn failover time
I have set up an AlwaysOn with a primary and secondary replica on different subnets but I have been forced to use Registerallprovidersip set to 1. This causes the listener to only have 0 IP address ...
5
votes
1
answer
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Problem adding a new node to a SQL Server 2012 Failover Cluster
I tried to add a new node to SQL Server (2012 Standard) Failover, that is already installed on another node in Windows2012 Failover Cluster
I have an issue with non editable field wiht input for SQL ...
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Should Full Text Filter Daemon Service be a cluster resource?
Our newly installed and configured SQL Server Always On Availability Failover Cluster with SQL Server 2016 Enterprise Edition runs with four instances and six nodes. It includes the DB Engine Service ...
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Mysqlfailover command - No slave is listed in health status
I have successfully created replication using GTID_MODE. It works perfectly. Now I need to setup automatic failover feature in it. I have run the following command.
mysqlfailover --master=root:abc@10....
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Postgres Streaming Replication: How to re-sync data in master (with standby) after failover
I am absolutely new to postgres 9.1 replication mechanisms.
I have managed to set up streaming replication between a master and standby postgres (Both have x number of records). At one point when ...
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1
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Replication throw an error after failover mirror partner is down in SQL Server
Received an error mentioned below after failover when mirror partner is down.
Error :
to fail over to a database which is not configured for database
mirroring. code: 22037, text: 'Invalid ...
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patching SQL Server with Availability Group and Secondary Replica
Scenario: SQL Server 2014 CU6. 1 AG with 2 databases (compatibility level 100). Failover Cluster with 3 nodes on Windows Server 2012 R2. Primary Availability Replica on node 1 and node 2. Secondary ...
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5
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Avoiding MySQL Fabric to become a single point of failure
I managed to install and configure MySQL Fabric that manages multiple MySQL Server nodes. It works very well since I tested it by connecting to the Master node directly and played with the data (...
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1
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AlwaysOn Availability Group Forced Failover
May I request your input.
I setup SQL 2012 with always on availability group for my databases in sync and secondary readable mode. I completed failover tests with sync mode and it is functioning as ...
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How do I switch master with slave and vice versa on MySQL?
I have two instances of MySQL, one master and one slave.
How can I switch them to make the slave the master and vice-versa while avoiding downtime?
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TDE in a SQL Cluster
I'm researchig into databnase encryption and whilst TDE seems to do exactly what it says on the tin, there seems to be no information on how to configure it up in a Microsoft failover SQL Cluster, or ...
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Force a Member to Become Primary when Primary fails in mobgodb
I have mongodb 2.6.11 cluster of two members: nms02 and nms01m. I know how to force secondary to become primary when primary is avail. But now my primary nms02 failed..and nms01m is secondary...How I ...
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MongoDB failover reasons
I have a replica set on MongoDB with 3 members - primary, secondary and arbiter. One day I came and saw that primary and secondary have switched. I'd like to find a reason for the failover that caused ...
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Restore Database on Active Passive Failover Cluster
Well, I helped my boss's boss install 2 nodes of SQL Server 2008 on a Windows server 2008 failover cluster. I did this remotely and I don't have accesse to it.
(I run a active-active cluster on Server ...
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Is this procedure to Failover to Logshipped secondary and Fail back again procedure correct?
I have a primary database in Amsterdam (AMDB), and a secondary in London (LNDB). I want to fail over from AMDB, to LNDB and then back again, without having to make another full backup (because the ...
4
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1
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Complete Failover Cluster Failure SQL Server 2012
We have experienced a full cluster failure on our 3 node cluster running SQL Server 2008 R2 with 7 SQL Server instances. It started when we rebooted one of the nodes and it returned an error:
Node '...
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Safely promoting master to slave
Previously I've asked the similar question MySql Switching Masters During Failover with log-slave-updates.
Let's say this is our current replication
In addition, I have few application servers. ...
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SQL Server DR Plan - Test Documentation
I have been tasked with creating a document for the testing of our DR/BC Plan for our SQL Servers. We are using DB Mirroring (tier-1) and transaction log shipping (tier-2) and for tier-3 databases we ...
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SQL Server - Company wants HA for single instance with 1 userDB - sanity check and questions
I am new to SQL Server (2 months) and learning at a gov company (europe).
The job is to make a HA solution for this 1 productive instance (1 database).
Following is given
SQL Server 2012
Windows ...
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Can you upgrade a single SQL Server 2008 Failover Cluster Instance to SQL Server 2012?
Or do you have to upgrade every FCI on the Failover Cluster? The documentation doesn't seem to be clear.
We have a 7 instances on a 3 node cluster. We want to upgrade only one of the instances from ...
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Are there any best practices before moving SQL Server to another node (controlled failover)?
Let's say there are multiple jobs running on the SQL Server - we have index maintenance jobs, backups, replication, etc. We would like to perform a switchover using Failover Cluster Manager. Are there ...
user6426