11 votes
Accepted

What to do when your Always On cluster loses quorum?

AGs are based on Windows Clustering. The WSFC procedures for quorum loss apply. WSFC Disaster Recovery through Forced Quorum Force a WSFC Cluster to Start Without a Quorum Once the WSFC is running, ...
  • 51.1k
11 votes

Accidentally overwrote mysql database with empty data

No, you can't. You have overwritten the database so your best course of action is to restore from the latest backup. If that is 4 months old, that's it, you lost 4 months of data. You should take ...
10 votes

Why is Full Recovery model a requirement for an Availability Group?

There is no point in HA if anyhow DR technologies are allowed in simple recovery. Transaction log is a must for point-in-time recovery. The transaction log is what a DR technology uses to replay ...
  • 18.4k
10 votes
Accepted

Always On FCI vs Always On Availability Groups

What is the advantage of Always On Failover Clustering vs Always On Availability Groups? The main advantages given 2012->2017 for an FCI is: No instance level metadata or objects required to be ...
10 votes
Accepted

Is there a way to back up agent jobs?

SQL agent jobs are stored in the system msdb database, so backing up that database will do what you need. In a disaster, you can restore the entire msdb database, or, if necessary, recover individual ...
  • 9,654
9 votes

What is the best option for High availability on a data warehouse?

Most data warehouses are in Simple recovery model, and most true HA solutions require Full recovery (AGs, Mirroring). The minimum for Log Shipping is Bulk Logged, but that's not really true HA since ...
  • 34.5k
8 votes

SQL Server 2012 Standard Edition Disaster Recovery Options?

Could you please let me know the best option to proceed and least complexity to maintain Logshipping is your best option for Disaster Recovery since you are on standard edition. Make sure you test ...
  • 61.4k
8 votes

Why is Full Recovery model a requirement for an Availability Group?

It's because these methods rely on the transaction log, which itself is only reliable in the full recovery model. Please read the following page in its entirety, as there are several hints there about ...
8 votes
Accepted

PostgreSQL ANALYZE execution time over 24h (still running)

After several hours of research and examining the current situation I think I managed to solve the issue. (Many thanks to fellow user ypercube for the inspiration and for Erwin Brandstetter who in ...
  • 171
7 votes
Accepted

Recommended mirroring alternative?

It sounds like you may benefit from a Failover Cluster if all you're looking for is availability. You can run them on standard edition and if you take an N+1 route, you can have two nodes for HA and ...
  • 388
7 votes

Is there a way to back up agent jobs?

Another way is to just export to file using dbatools Get-DbaAgentJob -SqlInstance workstation\sql2016 | Export-DbaScript you can even script out your entire instance or subset including agent jobs,...
  • 61.4k
6 votes

Why is Full Recovery model a requirement for an Availability Group?

Suppose I run the following query on a database with a recovery model of full: INSERT INTO dbo.MY_FAVORITE_MSFT_EMPLOYEES WITH (TABLOCK) SELECT 'SEAN GALLARDY' UNION ALL SELECT 'JOE SACK'; Under the ...
  • 30.9k
6 votes

What to do when your Always On cluster loses quorum?

What to do when your AlwaysOn cluster loses quorum? I have been into this situation especially with Multi-subnet clustering spanning different countries (NY-LD-HK). How to avoid Quorum Loss in a ...
  • 61.4k
6 votes

Why do I need witness in WSFC with two nodes?

Straight from the docs, with a two-node cluster without a witness: One node's vote is zeroed, so the majority vote is determined out of a total of 1 vote. If the non-voting node goes down ...
5 votes
Accepted

Disk Crashed, NDF(Index) file lost

Is there any way to fix database, without restore? No, you will have to do a restore. Please see this reference on how to do file and filegroup restores.
5 votes
Accepted

SQL Snapshot Redirect

One approach is to create a database containing only synonyms referencing the objects in the snapshot you need for reporting. Clients can then connect to the synonym database and run queries just as ...
  • 24.7k
4 votes

Disaster Recovery Options for Sql Server

During Hurricane Sandy (natural disaster) and recently when moving our data center (managed failover), I was in your situation. I have implemented Logshipping and was able to efficiently failover ...
  • 61.4k
4 votes

Oracle: Recover source code/table structures from "utterly wiped out" development database

UPDATE In order to start the instance without interfering with an existing running instance (e.g ORCL), before starting anything: sqlplus / as sysdba create pfile='/tmp/initORCL2.ora' from spfile='?/...
  • 38.6k
4 votes
Accepted

what exactly does an RMAN backup do?

In the simplest case, when you restore a database, you tell RMAN to recover it to the most recent point in time by applying all the redo (archived and online) that is available. That will re-apply ...
4 votes
Accepted

Recover deleted table from the database

You can restore the BACKUP with a different name in the same instance and follow steps below. 1) restore the database ( right click on databases > Restore ( it can be in the same instance )) with a ...
  • 7,156
4 votes
Accepted

Replication Madness

Please don't. You don't want replication. It's a data distribution technology: it's not suitable for HA. Just to name one of the many shortcomings of using replication for HA, you won't have automatic ...
4 votes

SQL Server AlwaysOn Error:35250

This is login and permission related error. What kind of account are you using to connect when you build the AOA features? If you are using a domain account you can fix this error it in two ways. ...
4 votes
Accepted

Business Continuity Plan -- How can I connect to DR Server if PROD site is completely Down

If you have: 2 Datacenters 1 Server in Each DC Using SQL Server AlwaysOn Availability Groups Then the following happens: The Primary Datacenter Goes Down, Completely How do you continue business ...
4 votes

Attach ldf more current than mdf

You should always produce a log backup before restoring a database. Call it a tail log backup if you wish. I call it "the last log backup before a restore". If you can't start your SQL server, ...
4 votes

How to maintain a query that runs forever?

It would be easier to mod the script so that it writes out either the last value, or a value every n times so that you can restart the script with the last known value in case of failure. Linux ...
  • 134
4 votes
Accepted

How to maintain a query that runs forever?

1st thought You have an XY Problem. You need to use an algorithm that allows you to restart from a specific point. Code Review Dividend.num <=@endnum exists in two places. Get rid of the 2nd one ...
  • 4,726
4 votes

Log files in Always on Disaster Recovery Situation

Is there any way I can handle it better than just letting the log files grow? I believe you have the ideal options covered already. You either Let the log files grow for the duration of the outage, ...
  • 27.8k
4 votes
Accepted

How do I recover data from the postgres data directory on my hard drive?

If you need a method to restore the database but do not have an Intel/AMD-based system available, then a virtual machine on Amazon, DigitalOcean, or elsewhere may give you what you need. If you’ve ...
  • 1,853
3 votes

Single node SQL Server 2014 cluster at DR environment

Overall, there is no need for a cluster IMHO. If you need HA at the DR site, then do it - but if you don't, I don't see a purpose for it as the stand alone will work just fine. The reason I say this, ...

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