Application With AlwaysOn Read Only Replica In Synchronous Commit
Mar 8, 2015
I am trying to implement a read only replica to move much of the data read for an application to the secondary replica. Initially I had the the primary and secondary set to asynchronous commit. QA brought up an issue with creating entities from the application because after the creation of an entity the application turns around and repopulates the entire aggregate object. Well it seems that the application was reading the secondary replica before the data had been committed. Although I understand the issues that synchronous commits can cause, I went ahead and made the change as I expected it to fix the issue. After changing the primary replica to synchronous we still had the error, so I also changed the secondary although that makes no since, but the issue remains.
View 5 Replies
ADVERTISEMENT
Mar 28, 2014
What happens when an automatic failover occurs, in a two server AlwaysOn Availability Group configuration, where the secondary replica is configured as read-only?
Will it only allow read-only connections, or will it become read-write and can accept INSERT, UPDATES and DELETES when assigned the new role as Primary?
Is it correct that adding a third server/node, that just acts as passive and should be used for automatic failover, to support true HADR, would NOT need another license .. and that licenses would only be required for the previous Primary and Secondary (Read-Only) replicas?
View 3 Replies
View Related
Jun 22, 2015
Having an annoying AG/AO problem with the read only routing side of it.
Let me give some specifics first:
2 SQL Server Instances, Not Clustered.
Availability Group is named 'Ireland'
There is a primary Replica and a Secondary Replica, named:
'IrelandPrimary' and 'IrelandSecondary'
There is a listener configured with the name 'ListenIreland' on Port 14330 (the two 3's are correct)
Read Only Routing URLS are configured as follows:
IrelandPrimary tcp://Ireland.dom.local:49891ALL
IrelandSecondary tcp://Ireland.dom.local:49841ALL
So now my problem:
When I try to connect using the ApplicationIntent=Readonly; or even using -K ReadONLY in sqlcmd I get the error telling me that my connection was actively refused.
This is connecting to the Listener, not the instance itself - that works fine. I'm at a bit of a loss now.
To explain what I am trying to achieve is a for a connection to be redirected to the secondary replica when its set for read-intent.
I've just noticed that it only fails when I specify ApplicationIntent=ReadOnly; If I omit the Intent It connects to the read-write database instead.
View 3 Replies
View Related
Oct 8, 2015
We have always on setup in our environment with read only replica. The primary database has 2 schema one is a dbo and other xyz. We have some store procs created in dbo schema and xyz schema. These store procs are being used by SSRS reports to retrieve the data (select only) no data changes will be made.
when we run the store proc from the read only server the storeprocs in the dbo schema run fine but xyz schema are failing with the message saying failed to update the database as this is a read only...
View 1 Replies
View Related
Nov 10, 2014
We are seeing high number of hadr_sync_wait types on our server after setting up AOAG during peak times. We have setup sync type as synchronous commit and failover automatic. Can we change these settings to async and manual failover whenever we need and change them back to sync commit during off peak timings. Any drawbacks because of these changes ?
View 4 Replies
View Related
May 14, 2015
is there any limition in AlwayOn to add database in secondary replica?
View 2 Replies
View Related
May 21, 2013
I have an AlwaysOn Availability group configured between 2 nodes (Synchronous)
Automatic failover was working fine until recently
I can failover between the nodes manually but automatic failover doesn't seem to be working. In my earlier test, I would shut down the SQL Service on the primary and within seconds, the secondary replica would take over. Recently I have performed the same test and the secondary replica enters the resolving state and the DB in unavailable.
I have tried everything here: [URL] ....
The only change I made was changing the availability mode from Synchronous to Asynchronous - Could that be the cause?
View 3 Replies
View Related
Apr 11, 2014
Looking for info on ole/requirement of primary and secondary replica under SQL Server 2012 AlwaysOn.
View 4 Replies
View Related
May 6, 2014
How can we change the backup replica in Always on Cluster. I am not able to take backup because of this.
View 7 Replies
View Related
Aug 19, 2014
After failing over to the DR replica. All databases are out of sync. DR replicas were setup as async the other 2 are set up as sync. Is this by design. No data has been updated to any of these as they are test dbs. So all dbs should be the same, no data loss.
View 0 Replies
View Related
Jun 17, 2015
I would like to setup replica for one of the databases for reporting. The current environment is a 2 node cluster(active/passive). I would like to add a 3rd node that can server as a secondary replica. The secondary replica will be on asynchronous commit mode.
The database that needs to have alwayson setup has column level encryption enabled.
Other Questions,
* Do I need to backup and restore the service master key on secondary server in order to have the column level encryption to work on secondary server?
* What would be preferred Quorum settings?
* What is the setting for 'readable secondary' for primary and replica db?
* What should be the setting for 'Connections in Primary Role' for primary and replica db?
* We are trying to setup without a Listner. Do I need to setup AG Listener? Can the application exclusively use the [secondary instance name].[replica DB name] without a listener?
View 4 Replies
View Related
Aug 6, 2014
I was working on a job to send me info each morning about database file free space and was noticing some odd things when looking at the log file VLFs for one of my databases in an AlwaysOn availability group.When I run DBCC LOGINFO on the secondary replica for this database, I get what I expect and most VLFs have a status of 0 (indicating the VLFs are reusable or unused). When I run DBCC LOGINFO on the primary replica, all of the VLFs have a status of 2 (active or recoverable).
Since log backups on the secondary replica in AlwaysOn still truncate the log in the primary replica, I would expect that the VLFs in the primary replica would also be mostly in a reusable or unused state. My log file sizes are the same size on each server and my backups are completing successfully. what might be causing the VLFs on the primary replica to have a status of 2 in DBCC LOGINFO when taking log backups from the secondary replica?
View 6 Replies
View Related
Feb 1, 2015
We have a 2 node clustered instance(SQL 2014) with 26 databases and we would like to enable alwayson for one of the databases for reporting (only one secondary and do not need high availability setup). I'm thinking if the reporting application/queries can explicitly connect to the secondary database(Instance namedatabase name) without using a listener and setup the secondary in asynchronous commit mode. Read about the REDO thread blocking due to reporting workload. How does this affect if I implement the secondary in this way.
View 3 Replies
View Related
May 22, 2015
I'm getting an error adding Replica to SQL AlwaysOn failover cluster in the new availability group wizard. When I enter the name of the target node (secondary replica) server and press connect, I get the following:
A network-related or instance-specific error occurred while establishing a connection to SQL Server.
The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 2) The system cannot fine the file specified
The SQL Browser service is up and running on the target. I am using an Azure VM for my SQL instance. This cluster spans geographies from our on-premise site to Azure via a VPN. This is a multi-subnet cluster. I'm attempting to create a new AG from the primary replica node and the target is a node on Azure called SSASNodeAz03.
[URL]
Full error:
Connect to Server
Cannot connect to ssasnodeaz03
Additional information: A network-related or instance-specific error occurred while establishing a connection to SQL Server.
The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 2) The system cannot fine the file specified
View 8 Replies
View Related
Oct 1, 2007
I'm new to SSB, so please bear with me. Our application requirements are:
1) Web app gathers user input from a web UI.
2) Web app calls a stored procedure, passing in the user input gathered in step (1).
3) Procedure issues queries to multiple data sources (SQL Server 2005 db's) derived from the user input.
4) Procedure waits for replies from these multiple data sources, governed by a timeout in case a data source is unavailable or slow to respond.
5) Procedure aggregates the data returned in step (4) from multiple data sources into an XML document.
6) Procedure returns the XML document as an output parameter.
This is different than the usual SSB asynchronous application paradigm. In particular, I'm wondering:
How can I setup a synchronous dialog, where the procedure that issues the SEND waits for a reply from the target service? I don't want the initiator procedure to end after SENDing, but rather wait for the replies to those messages so it can aggregate the data from the reply message bodies.
Thanks - Dana Reed
View 4 Replies
View Related
Dec 1, 2014
We are currently using 2008 environment. We do have an SSIS Package running. The package used to run everyday and take the production server full backups and restore into the another server. Then do some delete commands and do some updates in that database on that server (We have some sensitive data other than Production we have to run that scripts in any environment). After run all those delete statements another team will read the data from that database.
We are planning to migrate to 2014 and set up always on and use the replica as the source. In this case how the package will work?
How to change that SSIS package. With the 2014 always on we are directly reading the data there is no backups to restore then how to run the delete statements?
View 0 Replies
View Related
Sep 5, 2014
Setting up a test AlwaysOn Availability Group for one database.
However, whenever I restore the database to the replica server and join it, it ends up with my user account as the owner of the database.
Obviously I do not want a user account as the database owner, but since it is read-only I cannot modify it directly. If I were able to fail the AG over to the replica, I could change the owner then, but I cannot due to business requirements. this AG is to essentially serve as a replacement to log shipping.
I tried doing the backups and restores using EXECUTE AS login = 'sa', and yet it still shows up as my user account.
View 2 Replies
View Related
Aug 4, 2015
Background information: SQL 2014 Ent. highly volatile OLTP environment. We generate 10 - 12 GB compressed transaction log backup files every 15 minutes.
Currently - we have two-node A/P cluster residing on flash array. Need to leverage AlwaysOn to offload processing. Replica server with have Flash storage. Replica node has same CPU and memory footprint. 10GB connection between nodes. Anyone generating such large transaction log for 15/30 minute time period?
View 0 Replies
View Related
Jul 2, 2014
I have an availability group with read only replicas, readable secondary set to yes and allow all incoming connections. I have also configured the read only routing (at least I'm pretty sure this is correct).
If I login to SSMS with a user in the sysadmin role I can view the objects in the read only replica database. If I login with a user in the public role I'm unable to get past the obvious error:
"The database databaseA is not accessbile. (ObjectExplorer)"
I've also tried adding the "ApplicationIntent=ReadOnly" option.
View 4 Replies
View Related
May 5, 2014
Assume if i have a connection(Application intent readonly) starts with reading, writing and again reading data for a report. how it will works in SQL 2014 Always availability on?
View 3 Replies
View Related
Jun 30, 2015
I was hoping for some information regarding table triggers. We have databases that are part of an AlwaysOn availability group on SQL Server 2012. Some of the tables have table triggers defined. There are both types of triggers, INSTEAD OF and AFTER INSERT, etc.
From my understanding of how secondary read-only replicas work, I am assuming that these triggers have no impact at all when the database is a read-only secondary replica and they only fire when the database is the primary read-write database.
However, after doing a search on the internet, I have not been able to find a definitive source of information.
View 3 Replies
View Related
Oct 14, 2014
We have a reporting database which is refreshed daily from prod backup and later creating new tables/views/indexes as part of the refresh job. Is there a better approach we can implement in sql 2012/2014 for this scenario since we are planning to migrate to sql2014.
View 5 Replies
View Related
Sep 15, 2015
I have 3 servers taking part in an AlwaysOn AG.
I want to grant a user READ access to only one replica, and certainly not to the principle.
How do I go about doing this?
View 4 Replies
View Related
Jun 29, 2007
If application code controls all transaction processing to SQL Server, so it starts a transaction, does any commit or rollback on teh application side, how does that actually work ON SQL Server 2005... Meaning, If the app passes in a isolation level of Repeatable Read, and the database default is different, how can I see what is being used, as a DBA? Can I see any of that via Profiler? can I see when those commits/rollbacks are issued from teh application. They are not sending in "SQL" commit/rollback transaction commands. It's built-in to their architecture to control all that... How can I see what's happening on the database if these are not SQL commands for transaction handling? and how does that work, to start a transaction on the app side, and hold locks etc, on SQL Server if normal SQL Server commands are not being sent? If anyone can point me at decent references to read on that, thanks! Bruce
View 4 Replies
View Related
Jul 18, 2014
Considering trying to move 2008 acitve/passive cluster with log ship to day old read only 2008 server to 2012 active/passive to 2012 AG Read only server. Only problem is that read only instance may have to be a 2nd instance on a server. The new box is a beast 64 core 256 gig of RAM hp so this is no dog. So I have these choices
migrate 2008 active/passive cluster to 2012 active passive (this will be it's own ordeal)take new monster box and build two instances, one that will run the AG read only database, the other will house reporitng services and analysis services and a few dw databases. We are not heavy into deep dive analysis services yet kind of in it's infancy. Not sure if this other instance will be sql 2008R2 , may be able to do 2012. MY also have a few small sharepoint databases but they barely use it.
View 3 Replies
View Related
Nov 15, 2014
I setup an AG with a listener (AO1) on three servers.
Server1 = Primary, Readable Secondary = No
Server2 = Secondary, Readable Secondary = Read-intent only
Server3 = Secondary, Readable Secondary = Read-intent only
Connecting to AO1 with default settings, I end up on Server1.
If I attempt to connect to AO1 with specifying ;ApplicationIntent=ReadOnly (with or without specifying the db name) in SSMS, still lands me on Server1.
Also on topic, in this scenario I would actually want Server1 to be a readable secondary (in the event of a fail-over). So If I did set it as Yes, even If I do get the issue above working, won't I always land on Server1 then?
View 9 Replies
View Related
Jun 9, 2014
I have 2 SQL Server replicas configured on SQL Server 2012 AlwaysOn. e.g. SQL1 & SQL2.
I have configured backup job on both SQL Server with the following statement. and the job occurs every 10 minutes.
•declare @DBNAME sysname,@sqlstr varchar(500)
set @DBNAME = 'dba'
IF (sys.fn_hadr_backup_is_preferred_replica(@DBNAME)=0)
BEGIN
--Select 'This is not the preferred replica, exiting with success';
[Code] ...
I turned off SQL2 for Windows maintenance. So there is only SQL1 is online. Afterwards. I checked the backup folder and didn't see any new backup files was created after SQL2 was offline. I rerun the job. It still doesn't backup database on the Primary Replica. Then I searched on SQL Server Book online. It says
Prefer Secondary
Specifies that backups should occur on a secondary replica except when the primary replica is the only replica online. In that case, the backup should occur on the primary replica. This is the default option.
According to what it says, it should backup on the Primary Replica.
View 2 Replies
View Related
Aug 27, 2015
We have several read-only nodes in our AlwaysOn cluster, which are set to use Synchronous-commit mode, which ensures that the logs are updated on the read-only nodes before any update statements complete. Even with this option, if we query a read-only node before the logs have been processed, we can read old data. I would like to know a strategy to ensure that a read-only query will definitely return up to date information. I had an idea that if I just used a different transaction type, like Serializable, that it might block the read-only query from actually getting the data until after the log file was processed, but I have not tried it, yet.
I would like to move more queries to the read-only nodes, in an effort to offload CPU utilization from the primary node.
View 2 Replies
View Related
Apr 14, 2015
Here are my scenarios:
We have an application with replicated environment setup on sql server 2012 . Users will have a replica on their machines and they will replicate to the master database. It has 3 subscriptions subscribed to the publications on the master db.
1) We set up a replica(which uses sql server 2012) on a machine with no sql server on it. After the initial synchronization(used replmerge tool) the mdf file has grown to 33gigs and ldf has grown to 41 gigs. I went to sql server management studion . Right click and checked the properties of the local database. over all size is around 84 gb with little empty free space available.
2) We set up a replica(which uses sql server 2012) on a machine with sql server 2008 on it. After the initial synchronization(used replmerge tool) the mdf file has grown to 49 gigs and ldf has grown to 41 gigs. I went to sql server management studio , Right click and checked the properties of the local database. over all size is around 90 gb with 16 gb free space available.
3) We set up a replica(which uses sql server 2012) on a machine with sql server 2012 on it. We have dropped the local database and recreated the local db and did the initial synchronization using replmerge tool. The mdf file has grown to 49 gigs and ldf has grown to 41 gigs. I went to sql server management studio , Right click and checked the properties of the local database. over all size is around 90 gb with 16 gb free space available.
Why it is allocating the space differently? This is effecting our initial replica set up times.
View 0 Replies
View Related
May 8, 2006
hi
i have a problem with reading sql mobile database existed on the pc
i made a sql mobile database connection with ( Add New Datasource ) and then set
the datasource of dataviewgrid to display the returned dataset .
at run time i have an exception said :
cann't find the library with the name sqlceme.dll as i remember ,
can you help me solving this problem because i very need this step , please ?
regards
View 4 Replies
View Related
Oct 29, 2005
Hi,I've got this dts package in sql server 2000 sp4 that has severaltransformation tasks with an oracle database (10g) as the destination.The package executes successfully when run through the dts designer butwhen run using dtsrun, I get the following error at the completion ofall tasks in the dts package. The data inserts into the oracle databasebut i always get this Application errorThe Instruction at "0x7c8327f9" referenced memory at "Oxffffffff". Thememory could not be "read"Does anyone know how I can fix this?ThanksLyn
View 2 Replies
View Related
Dec 5, 2005
Server Error in '/' Application.
Database 'C:INETPUBDEMO.TRUTHSTONE.COMAPP_DATAASPNETDB.MDF' cannot be upgraded because it is read-only or has read-only files. Make the database or files writeable, and rerun recovery.Cannot open user default database. Login failed.Login failed for user 'NT AUTHORITYNETWORK SERVICE'.
Hi,
Strange one. I have copied my working web-site to the production server and get this message.
Tried copying new set of database files and reset the server to ensure no applications could be accessing the database files. Still get the same error.
Works fine on my Visual Studio VWD Express version.
Mitch
PS I am not trying to upgrade the database, just use it!
View 1 Replies
View Related
Nov 30, 2015
My application supports a single database connection and in the app console I can produce reports. If I include the app database in an AlwaysOn availability group with a read-intent replica will SQL automatically route the “selects” to that second instance thus offloading my application’s reporting activities or I need a separate db connection (maybe from a reporting app or cli) with a connection specifying read-only intent?
View 4 Replies
View Related
