Recovery :: Active Second Replica Shared DB Not Accessible
Apr 27, 2015
I have Active Active Cluster with 2 nodes , on the first node I can execute the queries, but when I trying to execute query or just open a DB to see the tables I getting error:"The Database XX is not accessible. (ObjectExplorer)".
We are trying to set up an active/active configuration of a SQL Server cluster, and we had a few questions.
Initially, we want to have 2 Database Servers that would share the same Database (both reading/writing to the same tables). However, from reading the MS docs, we find out that we can have what they call an "active/active" configuration using a Cluster but they need to have 2 different disk sets, i.e. having 2 separate databases. If this assumption is correct, how does the data get synchronised between the 2 databases (that are on the 2 different disks sets)?
One of our production databases was setup mirroring, log shipping and replication on it, the log file was setup unrestricted growth. This morning one index rebuilding process generated lots of logs, and the log file disk ran out of space, the database was in recovery mode. so we had to disable log shipping, pause mirroring and replication, expand log file disk, restarted SQL instance to fix the issue. Now we want to setup the log file to maximum size 80G, the whole log file disk is 120G.
So if the log file reached 80G next time, we can change the max size to 90G or 100G and it's easier to fix the space issue. My question is, if the database log file reached max size,
1. is the database still available? 2. Will the active session causing the issue be rollback to release space back?
As per our client requirement we want to set synchronization time from primary replica to secondary replica after 20 minutes. Is it possible in MSSQL AlwaysOn Availability Groups in SQL Server 2012?
I have 3 synchronous AlwaysON replicas: A, B and C. A is primary, B and C are secondary and both are set to Automatic recovery. How can I understand, which of them (B or C) will become primary when A goes offline? Well, Actually my final DB system should support following configuration:
1) Normally - A is primary B and C are sync secondary. 2) if A fails, B automatically becomes primary, C remains Sync secondary. 3) if A goes online, it becomes primary again 4) C becomes primary only after A and B fail (and there still should be cluster quorum!)
As I understood, first of all i should configure quorum the following way: A-0, B-1, C-1, folder-witness-1.
The problem, again, is: I cannot understand how to configure which replica becomes primary when AG fails over.
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
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';
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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.
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.
1. In alwaysON fail over cluster, Once fail over to secondary replica, what will happen to connected session in primary node? can the session fail over to secondary seamlessly or need to re-login. what happen committed transactions which has not write to disk.
2. Assume I have always on cluster with three nodes, if primary fails, how second node make write/ read mode.
3. After fail over done to 2nd secondary node what mode in production(readonly or read write).
4. How to rollback to production primary ,will change data in secondary will get updated in primary.
I have a table with the following columns employeeSessionID, OpDate, OpHour, sessionStartTime, sessionCloseTime. I need to see how many users remain active per hour. I can calculate how many logged in per hour, but I am stumped on how to count how many are active per hour. I have a single table that stores login data. I have created a query that pulls out the only the data needed from the table into a temp table using this query. Also note it is possible that the sessionCloseTime is null if the device has not been logged out this would need to be counted a active.
TABLE NAME #empSessionLog Contains the time stamp data OpDate, sessionStartTime and sessionCloseTime. OpDatesessionStartTimesessionCloseTime 2015-01-202015-01-20 14:32:59.1302015-01-20 14:33:14.6299166 2015-01-202015-01-20 06:58:33.7302015-01-20 15:27:16.9133442 2015-01-202015-01-20 09:56:22.8402015-01-20 17:56:29.7555853 2015-01-202015-01-20 05:59:18.6132015-01-20 14:05:19.0426707
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can see how many sessions logged in per hour with the following statement:
SELECT opDate, FORMAT(DATEPART(HOUR, sessionStartTime), '00') AS opHour, Count(*) AS Total FROM #empSessionLog Group BY opDate, FORMAT(DATEPART(HOUR, sessionStartTime), '00') Order BY opDate, FORMAT(DATEPART(HOUR, sessionStartTime), '00') ASCResults: opDateopHourTotal 2015-01-20041
[code]....
Where I am stuck is how do I count the sessions that remain active per hour until the session is closed with the sessionCloseTime.
I am having some teething problems while installing SQL on a 3 node cluster. Within the Cluster configuration I have 3 Cluster Groups with each of them having their associated disk resources. All these disk resources physically exist on a SAN.
The actual cluster is running absolutely fine and I can access all the disks from their respective owner node. The problem only starts when I start installing SQL Server 2005 on this cluster. I specify the Cluster group from the Cluster Group Selection and choose the desired partition and then the error message pops up
"There is not enough diskspace on the destination disk for the current SQL Server data files. To proceed, free up disk space to make room for data files, or install the data files to a different drive"
But the disk I am trying to install it on is 264Gb and none of it is used. I have also tried to change it to a different disk within the same Cluster group but to no avail. I have even tried to install it in a different cluster group all together but I get the same error message.
I have googled around havent found anything so far. The disks have got full permissions for the account I am installing SQL with.
I am newbie in SQL Clustering. I have set up a Windows Server Cluster with 2 nodes and am having the following problem with Physical Disk resource for cluster groups:
My Default Cluster Group (named Cluster Group) has IP Address, Network Name, Physical Disk and MSDTC resources. In addition to that my Default SQL Server instance resources are also in this group. I had this initial set up for Active/Passive mode.
Now I am trying to set up a SQL Cluster in Active/Active mode. For this I have to install another instance of SQL Server in the existing cluster and make a separate cluster group for its resources. I made a new cluster group (SQL Instance Group) with an IP Address and a Network Name resource for this new instance but I dont have any Physical Disk resource to allocate to it. As such while installing the SQL Server Instance I get stuck when I'm asked to select the quorum disk to be used.
Is it possible to configure two quorum disks, one for each group? What's the concept of dedicated disks resource for each sql instance in a group? Is this same as the quorum disk? If this is not a shared disk how do I configure a dedicated disk resource for my second cluster group (SQL Instance Group)?
We are going thru the process of scoping an active/active cluster at one site. I was wondering whether there will be any issues with mirroring (DB by DB) off the cluster into non clustered server at an alternate DRP site.
have you ever heard of an Active/Active SQL Sever 2000 Cluster deployed in a pure OLTP environment?
Some 8 years ago I have learned about a bespoke solution for the SAP ERP system (not the BW!) with DB2 Parallel Server for a huge German company. Then again, I would expect that Oracle RAC might fit into an OLTP environment, although I never heard about a real world implementation.
All this led me to believe clustering is good for failover purposes, and for decision support services, not quite for OLTP applications.
So if you see a point in Active/Active Clustering and OLTP please come forward and explain.
Cheers,
Johann
P.S: For those of you who want to know: Consultants from www.hiltes.com want us to deploy an Active/Active Cluster for their Fashion 3000 Net stock software.
We run several SQL 2000 SP4 instances on IA64 active/active cluster. The OS we run with is Windows Server 2003 SP1. We have different network cards : 2 network cards teamed for production purposes in domain X and 1 network card dedicated for problem solving in domain Y. First we configured the cluster with only the 2 teamed network cards for production purposes in domain X. Later we introduced the second network card for problem solving in domain Y. Everything looks fine. The (virtual) SQL instance listens on two different IP adresses on TCP port 1034. If we try to make connection via isql, EM or Query analyzer than we can directly contact the SQL instance from a workstation/server within domain X but this doesn't work form a workstation/server within domain Y. However if we use the specific TCP port in the connection in domain Y the connection is setup. We wish however not to use explicit TCP ports in setting up connections. Has anyone experienced the same problem before or has anyone an idea how to solve the problem?
I have a 2005 active/active cluster and want to apply SQL server 2005 SP2 to both node. I know that for active/passive , the sp can simple be installed on the active node(instance) and everything will be replicated to the other node. bear in mind what I have SSIS and SSAS and SSRS running on the active/active cluster.
what is the rigth method for applying the SP to activeactive cluster?
We some how is not able to entre to sql executive with the sa name and password and so not able to see the context of the database. we are not able to access the databeses either. We want a solution whereby I can change the SA login or give him the administrator right to do everything with the database.
Hi, i use sql server express 2005. There are several databases which all works fine. My problem is: when i try to expand one database in Management Studio express, i get for that database (not for others): "the database 'mydb' is not accessible (microsoft.sqlserver.objectexplorer)" and that's it. I can't see tables nor any objects of that db, while the application still can insert records into tables of that db. When i run this query: select * from master..sysdatabases i see all the databases (also 'mydb') with the same mode, status ... Thanks Tartuffe
I changed the Administrator Password on our Server. I also changed the sa password for the SQL Server to match. Ever since then, if one of my web pages attempts to retrieve data, the user get the error:
SQL Server does not exist or access denied.
This is strange because my pages do not use the sa account in order to retrieve data. I have a copy of MS Access installed locally on the server. Using it I can access the SQL Server data with linked tables. So the SQL Server is obviously servicing internal requests.
I tried changing the passwords back again, but the problem still persists.
Hi While configuring an active / active cluster, do I need to run the SQL setup on both nodes? The SQL2K setup installs binaries on localdisks of both nodes - hence the question.
I have setup an active/active clustering environment for SQL Server, however it is 2 seperate virtual servers. How can I set them up to exist as one virtual server containing both active installations? Can this be done? I have two compaq 8500 w/8 processors each. I need to be able to cluster these configurations to take advantage of all 16 processors in one virtual SQL Server. Can it be done?
If you can answer these questions, you will have my undying gratitude.
Hi I am running some tests on SQL7 in an active/active cluster and have a couple of queries 1. When I create an ODBC DSN, why is the "Use the Failover SQL Server if the primary SQL Server" checkbox disabled 2. To test, I was running SQL queries from Access over the DSN created. When the Primary Server went down, I had to reconnect to re run the query - Is this normal? 3. Can someone point me to any documentation on the above scenario that would shed some more light?
I currently have a two node HP hardware active/active cluster server. Running windows NT 4.0 Enterprise and dSQL server 6.5 sp 3. I want to upgrade the cluster to SQL 7. I would like to know if anyone ran into any problems or has sucessfully attempted this.
Also I read a few months ago about a gottcha involving NT sp4 and SQL sp5a that would prevent a node from failing over. Has this been corrected and does it affect SQL 7.
Is there anyone who knows where I can get some information about installing an ACTIVE/ACTIVE SQL 2000 Cluster server (MSCS). I have no problem setting up an active/passive failover cluster.
Where can I get more information? Do I need two instances? Two databases? What's the difference between active/active and active/passive?
Hello, Can anyone please explain how the failover processes works on a sql server 2000 2 node active/active cluster.
Given the following You have 2 node active/active cluster NodeA & NodeB
Question 1. How many SQL instances need to be installed on each node?
2. If the answer to question #1 is one instance per node, then say if NodeA fails NodeB will take over all the resources of NodeA including the master database, How does that work , how can once instance (in nodeB) handle two master database i.e its own master database and the one taken over from NodeA.