Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [high-availability]

High-availability technologies mask the effects of hardware or software failure, so that perceived downtime for users and applications is minimized.

1
vote
0answers
14 views

Enabling FileStream in existing clustered servers in SQL Server 2012

I have heard that enabling FileStream in an already existing clustered environment is tough. I'm working on a consolidation project and currently analyzing the impact it will have if we migrated DBs ...
1
vote
0answers
17 views

AlwaysOn Replicas set to manual but failing automatically

My two synchronous-commit SQL AO replicas are set for manual failover mode but are failing over automatically. When I look through the logs and extended events, it looks just like what would happen if ...
0
votes
1answer
24 views

I am trying to achieve a Disaster recovery for Mongo DB

Right now i have a MongoDb HA in site one and i need another site with asynchronous replication enables in another location.This is a base plan of mine to achieve a disaster recovery . I dont have ...
0
votes
1answer
25 views

Security Considerations for AG vs Log Shipping

we are considering removing our log shipping server and adding another node to our Availability Groups. While I understand that this should be better cause it's a/synchronous and will move the data to ...
2
votes
1answer
64 views

MongoDB stepDown fails in a PSA Architecture

I have set up a MongoDB cluster using a 3-Member Primary-Secondary-Arbiter Architecture Environment: LXC containers Linux Debian Stretch (9.8) MongoDB server version: 4.0.6 MongoDB Containers: lxc-...
1
vote
2answers
26 views

Upgrade SQL Server 2014 AG to SQL Server 2017 AG

Is it possible to migrate SQL Server 2014 AG (Windows 2012, SQL Server 2014) to SQL Server 2017 AG (Windows 2016, SQL Server 2017) using rolling upgrade method? What I mean is Build 2 SQL Server ...
0
votes
0answers
44 views

Availability group - HADR_SYNC_COMMIT - slow synchronous commit [closed]

We see intermittent slow transactions in our production database coupled with high HADR_SYNC_COMMIT waits. The database is part of a four replica AG with one remote synchronous-commit replica and two ...
0
votes
0answers
5 views

Standby servers in Postgresql

I want to know how many standby servers we can create in Postgresql? Like in Postgresql we can create log shipping standby, streaming replication,hot standby etc..
0
votes
1answer
26 views

File Share Witness with 4 Node Cluster

I am building a cluster of 4 nodes along with a file share witness. Every month due to server updates the server that holds the file share will need to be rebooted. My question is while the file ...
2
votes
2answers
31 views

Making a server with multiple instances a member of two effectively independent clusters

We're in the early stages of planning a new database environment for our ERP and CRM applications (third-party). The goal is to use Always On Availability Groups for HA, rolling patches, read-only ...
2
votes
0answers
77 views

2 SQL 2019 Servers with High Availability Linux with a shared Linux SQL Express 2019 Witness

Is it possible to have two SQL Always on High Availability servers in datacentre A replicating to two servers in datacentre B with one Witness using Express with two availability groups (one for each ...
0
votes
1answer
21 views

Native MariaDb encryption and clustering

Is native (table/Column/tablespace) database encryption possible in a clustered environment. The success criteria would be: Encrypted Logs Encryption in transit for all data protocols Native DB ...
1
vote
1answer
46 views

how to find out the log backups that I need to restore in order to bring log shipping from standby to online?

I have log shipping set up from server1 to server2. on server1 transaction logs backups are taken every 15 min to a network share folder. these transaction log backups are then copied (afte 1 hour) ...
0
votes
1answer
37 views

Listener Port 1433 for Always on Availability Group

In our Availability group I have a reporting server where report writers will connect directly and also crystal reports will be used, If the listener port is 1433 and the clients also gets connected ...
0
votes
1answer
56 views

is this time to remove the databases from the availability group? which ones?

While patching one of my servers that is part of an availability group, as a secondary, I had some problems - the real problem was that the host machine of one of the virtual servers in the ...
0
votes
1answer
61 views

mongodb replica set No Election of Primary with 6 of 7 Nodes UP

I have 8 instances running on Scaleway , 5 for Data and 3 Arbiter. And the versions of mongo on them are such : mongodb2 (mongodb 3.4.9) mongodb4 (mongodb 3.4.15) mongodb5 (mongodb 3.4.15) ...
0
votes
0answers
50 views

SQL Server error 19456 when adding the listener

I have three replica same subnet both has a Private and public network. I was able to create the cluster and create the availability group . When I try to add the listener I get the below error ...
1
vote
0answers
20 views

Why use Failover replica on Google Cloud RDS?

we are thinking of migrating our MySQL database from our dedicated server to a Google Cloud RDS instance. However I would like to clarify the below: 1) What is the purpose of creating a failover ...
1
vote
0answers
40 views

Adding Databases to Availability Group

I'm attempting to add databases to an existing availability group using automated seeding but I randomly receive this error: "Seeding Check Message Timeout". I'm pulling this error message from sys....
1
vote
1answer
26 views

Enable Replication/CDC from High Availability Group

I am a newbie to this Replication concept and I am trying to build some scripts to automate our Build Process where we will be disabling/re-enabling Replication on a regular basis. Background: We ...
2
votes
1answer
54 views

Quorum question for SQL Cluster (Always On)

We are looking at setting up an SQL Always On High Availability environment at our organisation. Our organisation has two datacenters of with one much smaller one but this one's being created to ...
0
votes
0answers
96 views

MHA vs Orchestrator

Im going to setup an HA solution. Im planning to use Orchestrator. But seems MHA is also doing well. If anyone already used/using any one these solutions, please suggest me to choose a right one ...
3
votes
1answer
54 views

MYSQL database failover

Current status I have a MySQL (MariaDB 10.2) server with various databases, to which a lot of people have access to. Which means that users can create MyISAM or InnoDB tables/databases. Problem ...
0
votes
2answers
108 views

DR/Reporting solution for a large SQL Server database

We have a large (3TB) database that is a part of AOG. We now have a need for a third copy of the data. Here are some of things we need: The third copy needs to be in sync with the primary in real ...
1
vote
0answers
34 views

How do Master / Slave JDBC URL handle broken MySQL Slave?

I own the following classical MySQL 5.7 set-up : one master server one slave server The master => slave link is done though GTID. I'm monitoring the link by querying show slave status on the slave ...
1
vote
1answer
190 views

Availability Groups Failover Readinness “No data loss” and rollback of nonqualified transactions

I have Availability Groups with Synchronous Replication and Automatic Failover setup with SQL Server 2016 SP2 in my production environment. I want to do a manual failover for patching and I have ...
1
vote
1answer
43 views

Shouldn't Windows Server Failover Clustering already take care of SQLServer Failover Clustering?

After reading this question, Are "Always On Failover Cluster Instances" and "SQL Server Failover Clustering" the same thing? If Windows Server Failover Clustering is installed, ...
0
votes
1answer
19 views

Promoting MySQL slave with unknown replication delay

Consider I have a master on DC1 and slave on DC2. Now, DC1 network is completely down for indefinite time and I want to resume the service as soon as possible on DC2 by promoting the slave to master. ...
1
vote
0answers
56 views

Availability Group Always ON 2016 HADR_SYNC_COMMIT

I know it is not the best practice but we have a two node AG 2016 between two data centers. Server 1 and HQ and Server 2 at DR and they are clustered (multisubnet). AG is setup in Synchronous Commit ...
-1
votes
0answers
33 views

How do I determine the cause of a SQL 2017 Mirroring Login Failure?

I have two SQL 2017 servers set up to create a Read-only replica on the secondary. All was working, but suddenly without any user intervention, the mirroring has stopped. I am seeing the following in ...
1
vote
0answers
146 views

Mirroring on-premise SQL Server to AWS EC2 SQL Server

Trying to mirror an on-premise SQL Server instance to EC2 instance, but not much information is available on this topic. The closest one I managed to find is: Implement SQL Server High Availability ...
1
vote
1answer
85 views

Difference between High Availability data synchronization across local replicas and DAG

I see a significant difference when synchronizing data between Primary - Secondary and between Primary HA and Secondary HA as part of Distributed Availability Groups. The difference in the amount of ...
0
votes
1answer
223 views

How to set-up failover in Postgres 9.6?

I have two postgres server with a master-slave architecture, the slave is replicating the DB from the master. In case the master goes down, the slave takes over and becomes the master. Now, the ...
3
votes
1answer
48 views

Is there any way to add a witness without restarting the witness afterwards?

I want to add a third instance of SQL server to my mirroring pairs to act as a Witness. When I set the witness, the mirror remains disconnected from the witness and the mirror's log accumulates errors....
0
votes
1answer
262 views

SQL Server ReadOnly Routing Connection String

Can we route read-only connection to readable secondary replica without setting connection string (ApplicationIntent = ReadOnly)?
2
votes
1answer
322 views

Mongo CP, Cassandra AP?

I have read lot of articles on net but still confused why Mongo CP, Cassandra AP, RDBMS CA ? Will explain my understanding and query along with that . Mongo Consider a scenario where I have ...
1
vote
0answers
201 views

Patroni : How to handle a slave which has been disconnected from master for long time?

Let's say if I am using asynchronous streaming replication with the below configuration in a 3 node cluster with Postgres 10.4 and Patroni 1.4.4 bootstrap: dcs: ttl: 30 loop_wait: 10 ...
1
vote
1answer
284 views

AlwaysOn High Availability Take database offline from primary

I have below scenario where i need your help: I have configured the AlwaysOn High Availability on my server. I have two replicas. Now I have requirement to make one database offline from the primary ...
0
votes
0answers
42 views

Index full population with AlwaysOn

Getting an error when running: ALTER FULLTEXT INDEX ON MyTbl START FULL POPULATION error: Msg 7654, Level 16, State 1, Line 3 Unable to obtain the population status of the table or indexed ...
7
votes
1answer
96 views

Multi-homed SQL Server with High Availability Groups

We have two servers (SQL-ATL01, SQL-ATL02) that make up a Failover Cluster, each running as part of a SQL Server High Availability Group (HAG). Each server has two network cards. One is a 10Gbit card ...
0
votes
1answer
59 views

Availability Groups Service Account has over 25000 sessions open

I am running Availability Groups on SQL Server 2014 with one database in the group. Today, the server was responding very slowly and when I got on the server I found that the Availability Groups ...
1
vote
2answers
1k views

What reason could cause AWS RDS connections to

It's my first time using RDS on AWS, I use a t2.medium instance running MySQL Aurora with default configs. The CPU usage and DB connections is quite normal until "something" happen, which cause the DB ...
1
vote
0answers
113 views

What is a good schema for a database where users can search for inventory availability on certain dates (such as Airbnb)?

I apologize if this is not the right venue to ask such a question. This is my first time on this site and I'm open to suggestions. I am trying to find a good schema for a database that needs to ...
1
vote
0answers
57 views

Can I run an index rebuild on a sql server HA replica or a copy the DB, and then swap with the primary?

We have a large database hosted in sql azure and we need to occasionally run maintenance tasks such as index rebuild. Pretty common of course, and we also try to minimize downtime. We use the premium ...
2
votes
1answer
1k views

Always On FCI vs Always On Availability Groups

What is the advantage of Always On Failover Clustering vs Always On Availability Groups? Basic Always On Failover Clustering provides server level protection, (eg: 2 servers with 1 shared disk space; ...
2
votes
1answer
33 views

Cost of replaying transaction log on sql server HA replica

I've been reading about the sql azure scale out. I suppose it makes senses to leverage the replicas hardware for read-only workloads. But it got me wondering, which is actually doing more work? The ...
0
votes
0answers
182 views

pgpool failover not working

I have setup pgpool 3.4 with streaming replication setup.I have installed pgppol on both the servers,Below are my file contents pgppol.conf listen_addresses = '*' port = 9999 socket_dir = '/tmp' ...
0
votes
1answer
43 views

Quorum configuration warning for cross subnet AAG failover

We have setup a 3 node AAG in our staging environment as a POC. The 3rd node has been configured in a different subnet and also as an asychronous replica. The Windows Server version is 2012 R2 and the ...
0
votes
0answers
50 views

rh-postgresql96(Red Hat provided postgresql) vs postgresql-9.6 (community postgresql)

Our client has provided us Red Hat machine for setting up PostgreSQL. We are allowed to install red hat provided packages only. So we have to install red hat provided postgresql (rh-postgresql96) ...
1
vote
1answer
68 views

Failover Cluster, Availability Group, and Disaster Recovery

We have an active/passive Windows Failover Cluster setup as an HA solution. Here is an example of what that might look like: Cluster1: [Node1 'active', Node2 'passive'] We're looking to set up a DR ...