SQL Server Admin 2014 :: Load Balancing With Availability Groups
Aug 28, 2014
We are having a conversation at work and the subject of load balancing with SQL came up. Right now we are running SQL Server 2014 on four (4) machines. I am using a AlwaysOn with Availability Groups (AG). Now I know that we can scale out the reading in AG by allowing the secondary serves to receive reads.
Is there a way to be able to do this with writes? Can I have in essences 2 masters that some how reconcile with each other? We are expecting a huge amount of writes in the near future and we need a way for SQL to handle the amount of traffic we are expecting with out any issues.
I explored the possibility of Peer - to - Peer replication; however, it seems that it would be more work if we are constantly making updates to the database scheme.
View 2 Replies
ADVERTISEMENT
Apr 2, 2015
The MSDN doc makes it sound like after a failover of the primary, the CDC data won't "keep working" on the secondary unless you "To allow the logreader to proceed further and still have disaster recovery capacity, remove the original primary replica from the availability group using ALTER AVAILABITY GROUP <group_name> REMOVE REPLICA. Then add a new secondary replica to the availability group."
We have a few CDC tracked tables that we use and the general idea of AlwaysOn I thought was to minimize all the overhead and let things "just work" so your apps just connect and the listener re-routes everything where it needs to go.
It looks like to get this working properly an automated job /trigger would have to wait for a failover event and then kick off tasks to remove and re-add the replica and perhaps start up the CDC job on the secondary?
View 1 Replies
View Related
May 21, 2014
how does security works between availability groups.
ex if i create an object and grant permissions to a user will that be replicated to secondary replica .
View 4 Replies
View Related
Feb 11, 2015
we currently use Backup Scripts from Ola Hallengren, It Says Full (non copy-only) and differential backups are performed on the primary replica. Full(Copy-only) backups and transaction log backups are performed on the preferred replica.
we currently do FULL(COPY_ONLY) Backup everyday and LOG Backups for every 15 min, is there any performance benefit on running the FULL (non copy-only) on the preferred replica .
View 3 Replies
View Related
Sep 1, 2015
We have a server A and a server B setup with SQL2014 High Availability - working fine.
I need to add an additional listener to our new DR site.
What is the best way to do this without impacting production - can I just add the additional replica from nodea as a secondary replica?
View 1 Replies
View Related
Sep 15, 2015
I am planning to have AlwaysON Availability Groups setup between Server 1 and Server 2
Server 1 -->Publisher-->2014 SQL Enterprise edition-->Windows Std 2012 --> Always on Primary Replica
Server 2 -->Publisher(when DR happens)-->2014 SQL Enterprise edition-->Windows Std 2012 --> Secondary Primary
Server 4 as Subscriber
Server X as Remote Distributor ..
If i create Publications on Server1 (primary replica) to subscriber 4 servcer, will the publication be created automatically in Secondary Replica Server2 ? or do i have to create manullay using GUI/T Sql on Both Servers?
View 1 Replies
View Related
Oct 16, 2014
This is my first deployment of an always on availability group for SQL 2014 and I'm trying to get my custom backup procedure to handle all databases appropriately depending on the primary group. Basiscally I want the system databases and all databases that don't participate in the availability group to be backed up on both nodes and those that do participate backed up ONLY on the primary server. I've looked at the sys.fn_hadr_backup_is_preferred_replica funcation, but would like to only have to test for a single databases existance in the availability group. If the one database is in the group, only backup the system databases and those that don't participate, otherwise backup everydatabase. This would be the case for both full backups and transaction logs.
View 1 Replies
View Related
Nov 25, 2014
I want two write a small script to determine which is the currently active (primary) server in the AG.
Right now, I see that using SELECT * FROM SYS.dm_hadr_availability_replica_states I can determine the role. However, when the server goes down and switches to the secondary node, I don't believe that the role changes (or does it?). How do I determine which is the active node?
View 9 Replies
View Related
May 7, 2014
A little background on what I am trying to achieve first. We are moving to Azure virtual machines and we will have 8 disks on the SQL Server box. I am adding more files to the primary file group and each file will go on its own drive. I am then rebalancing data across these files by rebuilding all of the indexes on the tables which is working fine. No problems so far all is good.
I now have an additional problem. If there is a lob or blob column on the table, rebuilding the clustered index and all the non clustered indexes doesn't rebalance the blob or lob data across the disks such as it does with in row data.
I cannot find any articles on rebalancing lob or blob data because all the articles say to move to a new file group. I do not want a new file group, I just want to use the primary file group where the data already resides, and just redistribute it evenly in the same way that I can in row data which is working fine.
One solution I thought about was to BCP data out of the table, truncate the table and then BCP back into the table which I imagine would have the desired effect of distributing the data evenly over the files.
View 2 Replies
View Related
Jul 3, 2015
We have 4 servers : Server 1 , Server 2 and HA , DR servers.
I designed 2 Plans to get HA support for my databases .
Which of them are better , And is there any problem in my design ?
View 4 Replies
View Related
Aug 18, 2015
I am trying to create a job that runs against my High Availability listener server.
It is a fairly simple SQL statement in the job - execute tsql.
When I try and run the job I get the error:
Executed as user: NT SERVICESQLAgent$SQL2014A. The target database ('BB_Prod') is in an availability group and is currently accessible for connections when the application intent is set to read only. For more information about application intent, see SQL Server Books Online. [SQLSTATE 42000] (Error 978). The step failed.
I thought there was a way to run a select statement as a job against the listener? The tsql step is only a select.
Is there a way to pass in the application intent = readonly as part of my SQL statement?
View 2 Replies
View Related
Nov 10, 2014
Is there any way to trigger an event (ie. call a procedure/job/etc.) when/if an AG fails over?
Not looking to use agent alerts.
View 0 Replies
View Related
Dec 24, 2014
Recently after turning on trace I restarted the sql services on a box which is configured for automatic failover availability groups. The ag has not failed over to other node. The other node was in resolving state. When the restarted server is back, the AG went back to that server. I checked the sys.availability groups field for failover property failure condition level, it's set to 1 which means service restarts should initiate the failover.
View 3 Replies
View Related
Jun 17, 2015
What I asked for: Three Windows Server 2012 R2 machines with independent storage running a SQL Server 2014 AlwaysOn Availability Group. DB1 would be the primary, DB2 would be a synchronous replica, and DB3 would be a remote asynchronous replica.
What I was given: a two-node Windows Server 2012 R2 WSFC to run SQL Server 2014 Enterprise with shared storage and a third (remote) Windows Server 2012 R2 machine with independent storage, also with SQL Server 2014 Enterprise, to host an AlwaysOn Availability Groups asynchronous replica.
DB1 and DB2 (as Cluster1) share an E: drive. The remote DB3 has its own E: drive. Initially, DB3’s E: drive was claimed as a cluster resource and I couldn’t even see it. I’ve had several ugly days trying to make this work and have temporarily given up, installing DB3 as a standalone SQL Server that is no longer part of the WSFC and pointing everything towards that (it was originally a third node in the WSFC).
Is it possible to create an AlwaysOn Availability Group with nested clusters (i.e. create the AOAG with Cluster1 and DB3 and somehow ignore the individual nodes that comprise Cluster1)?
View 6 Replies
View Related
Jul 9, 2015
I have a situation where I need to rebuild indexes on a large DB (500G).
When I do a test run of the rebuilds in my test environment it uses 100G of space - which is fine with me.
When I do a rebuild in my High Availability environment - same DB, same script - it eats up over 600G of space and fills the volume.
What can I do without removing my DB from H/A to rebuild the indexes?
View 8 Replies
View Related
Oct 19, 2015
is there a way to restore all file groups except one? example: Database A has 10 filegroups, but 1 of them is defunct, so i cant delete it and there's no backup for restore it.Can I create a new DB restoring the 9 good FGs from a database A's backup?
View 9 Replies
View Related
Nov 14, 2014
Where can I find dates and times to when an availability group was moved outside of the SQL error log?
View 1 Replies
View Related
Nov 3, 2015
We are looking at going down the High Availability Always On route. However we have some concerns around the lack of support for MSDTC. In short we are concerned that developers may introduce functionality either on purpose or by mistake that uses the or escalates the Query’s to the MSTDTC. As this could result in database splitting.
Understand that this will be a moot point in SQL 2016 but for 20122014 is it possible to disable the MSDTC to protect against this and run High Availability Always On. ? Does it just need to be disabled on the SQL Server or does it need to be done on the application server ?
View 0 Replies
View Related
Jan 27, 2015
I Create an availibility Group with a primary and a secondary. (For test)
Then run Planed Failover.
Switched to secondary. That's ok.
After that I update some tables on secondary (That now is primary)
I Run Again Planed Failover on server 2.
Switched. OK
But primary database Get (Not synchronizing) Status.
And in primary I don't have that updates.
How to sync these databases and exit from Not synchronizing.
View 5 Replies
View Related
Jun 27, 2015
I setup an availability Group. (Only 2 servers - Primary And secondary) -- 21 , 22
I also define an listener . IP .. 23
1- In First step I connected To Listener (23) And in a while I inserted A record to a table .
While 1=1
insert into Tbl_T1(f1,f2) Values (1,2)
2- in second, I Stop the primary .
- I expected this while whitout disconnect, continue.
3- The while code stopped whit this message :
Msg 64, Level 20, State 0, Line 0 A transport-level error has occurred when receiving results from the server. (provider: TCP Provider, error: 0 - The specified network name is no longer available.)
4- I execute again the script, And it worked in new primary.
My questions :
1- is the listener disconnected between switched primary and secondary ? OR have we data loss between switching?
2- I did some huge update on Primary that fill the Log fiel space. And in last Update I got this error :
Msg 9002, Level 17, State 2, Line 27
The transaction log for database 'Your_DB' is full due to 'LOG_BACKUP'.
Is this (Fill All space) a reason to switch primary? Or not ?
View 2 Replies
View Related
Aug 14, 2015
I'm running a primary and secondary on sql server 2012 enterprise edition on windows server 2012, and it runs fine except when a network outage occurs.
Then the handshaking keeps failing, the databases on the replica show as not synchronizing and the only way to fix this is to reboot both primary and secondary.
We keep getting 3520's, etc. on the DR error log
How to eliminate all these prod reboots?
I increased query connection timeouts to 60, but saw no change.
View 0 Replies
View Related
Oct 7, 2015
how to load the data from oracle to sql server
oracle source is having 7 tables
sql server target is having 7 tables
i have used VISUAL STUDIO and created the one data for individual but how to run in sql server that ssis package
View 9 Replies
View Related
Jun 19, 2015
I am setting up extended events more or less just fine, however I am a bit confused as to how to read and load them into a table for querying. In particular the offset part - is there a way to load just a given dates worth in?
I've got the files configured to be 20MB before rolling over, the XE is running all the time.
So if i load in the full file now, say that covers 2.5 days worth, when I load it again tomorrow to get the updated data I'm also reloading today, which is a waste?
I presume I am going about this wrong, but lack an example that really goes into detail of practicalities of loading this data.
View 0 Replies
View Related
Jun 7, 2005
Hi!Currently we only have one SQL Server database in our production system. I would like to add one more SQL server 2000 database. I would like to configure them so that both server share the load and Failover. I did some research and I found that I can do this by installing the OS (Windows 2000 Server Enterprise Edition) and SQL 2000 Enterprise Edition on both machines using the windows clustering. I want both servers to be active. They both have a copy of the production data. What I don't know is that, if it is possible to synchronize the data on both databases using SQL Server Replication utitlites. From what I know one SQL Server must be Publisher and one Subscriber. Can one sql server be both? Because I want both sql server to be identical. Can I set up replication between more than 2 servers? We just need to add one server for now but I would like it to be expandable. In the future we may need more.So Please provide me some ideas and answers about the following.1- Can two SQL Server cross replicate (both update each other in order to be identical)?2 -Does replication work beyond 2 servers.?3- If you were to set up a production database; what do you recommend considering the load balancing and Failover using Windows 2000 Server Enterprise Edition and SQL Sever 20000 Enterprise Edition?Thanks,Michael
View 3 Replies
View Related
Nov 8, 2001
Hey guys,
Lately we have come across a problem where our application is undergoing some extreme load against the SQL 2000 server database we have setup, where the server is hitting 100% CPU utilization each time. Currently the box is a 2 processor box.
Here is the question I have. I have seen under most SQL Server clusters that an active/passive setup is implemented. Where the passive server just exists as a failover mechanism. What I am looking for is some information on how to setup active/active setup where each server receives processes to handle.
Has anyone created a setup like this? Are there any standard benchmarking tools that can be used to see how this configuration increases performance? Is this setup more favorable than going to a 4 processor server as oppossed to our current 2 processor server?
BTW: We have noticed that after a web application where the user sits idle for a while the SQL Server application loses the connection with the application user...Is this the SQL Timeout causing the connection to disconnect?
Thanx for any response...
Bri
View 1 Replies
View Related
Jun 16, 2006
We are beginning to design a new application with SQL Server 2005. Our current production environment is slated to be two SQL Server 2005 machines with the databases residing on an EMC SAN. We have requirements to both have automatic failover between servers for availability and also be able to balance the load over two hot servers for scalability.
Can anyone point me in the right direction for things I need to consider in order to be able to implement both of these requirements? Can I implement database mirroring (for failover) and transactional replication (for balancing) given the hardware configuration I'v mentioned? Is more information needed? Where should I turn next?
I am coming off a mainly Oracle background for the last ten or so years with a smattering of SQL Server mixed in. I've tried to hit the ground running on this project, but sometimes find myself hitting the wall running instead.
Thanks,
Larry
View 3 Replies
View Related
Jul 7, 2007
I have posted this also in one forum. Somebody might have idea here.
We have four Windows 2003 advance servers with SP 3 configured on NLB.
Each of them has one NIC.
Recently we started to get frequent time-out error messages from web applications on those servers when they try to establish the connection with the SQL 2005. If you run web pages application to connect to sql server 10 times, 9 times you will get good connection results and 1 time you will get time-out.
Microsoft OLE DB Provider for SQL Server error '80004005'
Timeout expired
/common/mypage.asp, line 20
Connection to sql server is established with the connection string. Any idea how to solve this problem? Is there a connectionproblem? from NLB to Web to SQL?
We have tried doing some suggestions (e.g. LMHOST, IP, domain account for WEb to SQL connection, the Query Wait in SQL advance property.), but seems this timeout expired still exist
Thanks in advance...
View 3 Replies
View Related
Jul 20, 2005
I will be doing some performance testing on financial application nextmonth. Without going into a lot of details, I suspect I will have apotential bottleneck when writing to the log file.My hardware setup is a quad 2.8 Xeon Dell server direct attached to aDELL/EMC CX200 (Fibre channel array with 10 X 30something GB, 15,000rpm drives, with about 1GB of memory on the array for caching.This is a benchmark environment, so I am not concerned about loosingdata. I am looking for a little guidance on using raid (0 or 10)and/or file groups to spread IO to db objects (log file(s), data,indexes, tempdb, etc). I have read about and played with file groupsenough to know that SQL server does some level of load balancingacross file, but am unclear it is in parallel or serialized.Common wisdom seems to be to separate data, non-clustered index, logs,and tempdb onto separate files, but I am unclear on how to make bestuse of the high-speed disk array. I'd greatly appreciate opinions onwhich would perform better; one file on a stripe set of N drives (raid0 or 10), N files in a file group placed on N (non-striped) drives, ora combination of the two? Is the answer the same for both log and data(or index) files?Thanks,-Bernie
View 6 Replies
View Related
Dec 1, 2015
I have configured replication between Always ON Availability Groups (Listener) (PUBLISHER), remote distributor to XYZ SUBSCRIBER...with above link ...
Now, I want to know how to replicate Data from XYZ SERVER a PUBLISHER to Always ON Availability Groups (Listener) (SUBSCRIBER)? Distributor Database being on XYZEX:
XYZ SQL SERVER as PUBLISHER, and DISTRIBUTOR
to
Always ON Availability Groups (Listener) SUBSCRIBER...
View 3 Replies
View Related
Sep 14, 2015
I am planning to have AlwaysON Availability Groups setup between Server 1 and Server 2
Server 1 -->Publisher-->2014 SQL Enterprise edition-->Windows Std 2012 --> Always on Primary Replica
Server 2 -->Publisher(when DR happens)-->2014 SQL Enterprise edition-->Windows Std 2012 --> Secondary Primary
Server 4 as Subscriber
Server X as Remote Distributor ..
as of now , In the event of Disaster happens on Node 1 i will have to manage JOBS on Node 2 (backups, Maintenance, replication, day-day other Jobs)..Is there a way i can call all jobs to run from a remote server which executes on Active NODE(which ever is active)? so that in the event of disaster happens on node1, when node 2 becomes online and i don't have to do anything with SQL Agent or jobs on Node 2?
View 4 Replies
View Related
Aug 27, 2015
I want to set up a database role so that users can use sp_readerrorlog through SSMS. It does a check on membership in the securityadmin role.
I have tested it and can see you can grant execute on xp_readerrorlog but the SSMS GUI uses sp_readerrorlog.
I thought I could create a user/certificate and add the signature to sp_readerrorlog but it's not permitted (likely because it's not a normal database object).
So the other solution is to add the users to the securityadmin role but then explicitly deny alter any login (best done with a custom server role in 2012+ but otherwise just manually in 2008). I tested this out and it works, I'm not able to alter any logins or increase my own permissions, I also did a check of what's reported from fn_my_permissions(null, null) and it shows minimal permissions like I'd expect.
View 0 Replies
View Related
Jul 9, 2015
I am setting up a 3 node cluster as part of an availability group.Initially I tested failover between nodes using SQL Management Studio and everything failed over successfully when I stopped a node, and I was still able to write queries. I started to test with an application which connects using an SQL user and whenever I would switch nodes, I would get login failed. I believe the cause of this issue is because the server logins SID's which are tied to the database are different than the server logins on the other nodes which resulted in login failed.how can I ensure that the server logins SID's are the same between nodes? Is there a way of copying this over or how is this supposed to be done? I read a little about contained databases where I could just set the login on the database itself vs. creating a server login but I would rather not go down that route.
View 4 Replies
View Related
Feb 27, 2006
Hello,
How is load balancing working in SQL Server 2000. We want to have two different servers as a back end for our web based eCommerce application. Is this possible? While there be any modification requirement in the application?
View 4 Replies
View Related
