If there is a history kept somewhere of failover events of a database in an AO group? I have 2 replicas with automatic failover and I'm looking for a history of failovers.
View 0 RepliesWe are planning to upgrade our production servers from mirroring to alwayson. Our current mirror setup gives the advantage that it can failover a single database.To have a similar setup in alwayson we are probably going to create an availability group per database. Any other disadvantage in this except for the extra initial configuration work?
View 9 Replies View RelatedI have setup SQL AlwaysOn between primary and DR data centers. Here is the setup:
Primary data center: Server1 (Primary), Server2 (Sync Commit Secondary), Server3 (ASync Commit Secondary)
DR data center: Server4 (ASync Commit Secondary)
Data synchronization and manual failover works fine. But, sometimes, the AlwaysOn cluster automatically fails over to Sync Commit Secondary on Primary data center. Here is the error message from Failover Cluster Manager->Cluster Events:
"Cluster has missed two consecutive heartbeats for the local endpoint xx.xx.xx.yy:~3343~ connected to remote endpoint xx.xx.xx.zz:~3343~"
"Cluster has lost the UDP connection from local endpoint xx.xx.xx.yy:~3343~ connected to remote endpoint xx.xx.xx.zz:~3343~"
I had our network engineer check all connections multiple times and he confirmed everything is fine. But he was also able to confirm (using monitoring tools) that right at the time of a failover, there is almost 2GB worth of traffic going from Primary Server to DR server. That happens every time. I had checked the times of all failovers and there is no job or process occuring that will produce 2GB worth of data. Also, this happens regardless of which server is primary.
Even though the failover works fine, this unexpected automatic failover due to missed heartbeats are occurring often (2-3 times a month).
Here is the list of errors from the Cluster Validation Report:
Under Network Section, I see the following error messages in Red:
Validate Network Communication
Network interfaces Server4 (DR) - SAN_Team and Server1 (Primary) - SAN_Team - VLAN 20 are on the same cluster network, yet address xx.xx.xx.pp is not reachable from xx.xx.xx.yy using UDP on port 3343.
Network interfaces Server4 (DR) - SAN_Team and Server2 (Secondary) - SAN_Team - VLAN 20 are on the same cluster network, yet address xx.xx.xx.qq is not reachable from xx.xx.xx.yy using UDP on port 3343.
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So I have 2 servers S1 & S2.
Database Group 1 = L1 with Primary S1 and Secondary S2
Database Group 2 = L2 with Primary S2 and Secondary S1
For 99% of the time the 2 groups of databases are not related. For the 1 procedure that does move data from L1 to L2 something like
Update L2.DB.Owner.Table
set flag = 1
Whare a = 0
On S1 I have a linkedServer with connection to L2.
If I have a failover I cannot have L2 on S2 as they are essentially the same server.
How to I use the 2 groups hand in hand.
I'm looking for a solution to have cross data center automatic failover in the event of a data center loss for highly critical databases. I would like to have local HA and also automatic failover to the DR site. This does not seem possible with AlwaysOn.
Is my only option for automatic cross data center failover to build a node in one data center and a node in the other data center with a node/FS at a third data center in order to maintain quorum? I'd like to have local HA in the mix but that doesn't seem possible.What pattern for the highest data security and also availability?
We are implementing a multi-site (Windows Server Failover Cluster) WSFC to enable Always On between our primary and DR site. We are not going to use SQL clustered instances. We are not planning to use shared disks. Each node is running a standalone instance of SQL 2012.
I have successfully configured a 3 node multi-site Windows failover cluster with no shared storage. For quorum, I have defined a File Share Witness (FSW). The FSW has voting rights and is in the DR site. The setup looks like this –
WSFC –
•Node A – Site #1 (voting right = 1)
•Node B – Site #1 (voting right = 1)
•Node C – Site #2 (voting right = 0)
•FSW – Site #2 (voting right = 1)
Again - There are no shared disks in our setup. We are not going to use SQL clustered instance. We are going to use Always On with these 3 nodes.
SQL Always On –
•Node A – Site #1 (Primary Replica)
•Node B – Site #1 (Readable Secondary)
•Node C – Site #2 (Readable Secondary)
All the setup including the “availability group” works properly under this setup. However, a failover to site #2 under DR situation is not working and I know why but don’t know what needs to be done to fix the problem.
The following works fine –
•Automatic failover between nodes A and B (same site – site #1)
•Forced failover to node C in site #2 provided at least one of the nodes in site #1 is up (non – DR situation) - this will ensure the cluster is up
The following is not working –
•Forced failover to node C in site #3 when both nodes in site #1 are lost (true DR situation) – This is because the cluster is not up at this point.
I know I have to bring the cluster up somehow and I have not been able to do so by restarting the cluster service.
I tried to run the command to start cluster service.
Question –
How can I FORCE the cluster to come up in Site #2 on node C when it has no voting rights?
I have always worked with even number of nodes and shared disks with traditional clustering. I am not sure what needs to be done in this scenario with 3 nodes and a FSW.
How can we find the cluster failover count in always on ?
As my AG is configured as synchronous mode , AG went offline and we manually restarted the AG service when we check the properties on AG role they r in default setting ?
An automatic failover set exists. This set consists of a primary replica and a secondary replica (the automatic failover target) that are both configured for synchronous-commit mode and set to AUTOMATIC failover.Configured the both AG Group database automatic failover and synchronous-commit mode.But automatic Failover failed also Cluster service not started automatically at Node2. It got connected through AO Listerner after starting Node1. As below SQL Error log during shutdown Node1
Date,Source,Severity,Message
10/27/2015 10:44:20,spid37s,Unknown,AlwaysOn Availability Groups: Waiting for local Windows Server Failover Clustering node to come online. This is an informational message only. No user action is required.
10/27/2015 10:44:20,spid37s,Unknown,AlwaysOn Availability Groups: Local Windows Server Failover Clustering node started.
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what need to be change existing AO configuration?
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?
1. 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.
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.
We had to failover our primary db server for maintenance to our secondary replica. The primary was rebooted during maintenance. We failed back after the maintenance and one of the databases is not synchronizing.
I checked sys.dm_hadr_database_replica_states, and it is showing that it is INITIALIZING.
It has been in this state for more than 45 mins now. The last_sent_time, last_received_time, last_hardened_time and last-redone_time are all stuck with a time stamp 45 mins ago.
They haven't changed. How do i resume this database and bring it back in sync?
I tried suspending and resuming the data movement, but hasn't worked.
I came across an issue while migrating from SQL 2005 to SQL 2012 and using AlwaysOn Group. For some strange reason, when ever i connect to the Listener name for each AlwaysOn group, it list all the databases which is on the SQL instance, so i would be able to see databases that is not part of that Availability Group. I am not using default port, so have to put the port after the Name to connect and both Instance and Listener are using different port.
Testing the fail over works fine too, when i perform a manual failover, i can connect to any of the databases in the group from my application with no problem.
Considering that the Listener Port is different to the port which the instance is using?
We are rolling out the use of Availability Group listeners to our SQL Server 2012 Environment which has a 2 node multi-subnet cluster. The Primary is R/W and the Secondary is a non-readable node that would be manually failed over to in a DR scenario
I have set up the AGL and asked the sysadmins to create a DNS record in both subnets with fixed IP's.
The issue I have having is that when I ask the app developers to connect to the databases using the AGL it is totally random whether the AGL resolves to the Primary or DR node - as a result that are having problems getting their apps to connect.
I was thinking of asking the sys admins to remove the DNS record in the DR subnet and then add it back in should we need to fail over - but I was thinking there must be a better way.
I have 2 servers in a SQL Server Fail-Over Cluster. IOW I use always-on availability groups. I run backups - full, diff and log - regularly via SQL Agent on one server only depending on which is primary. If there is a fail-over, then backups will continue on the other server. If I have to restore a database in an availability group I probably would need some combination of full, diff, and log backups from each server. Would that actually work? I test the backups weekly however I just realized that I never tested that scenario.
View 1 Replies View Relatedhow to resolve and trouble shoot the availability group is not ready for automatic failover in sql2012
View 4 Replies View RelatedLet's say I have a two node AG, Server A and Server B. Server A is normally the primary and Server B is the replica. Whenever the primary fails over from A to B or from B to A, I'd like to automatically run a script that will restart the SQL Agent service on the new replica.
View 3 Replies View RelatedI've setup a two node Cluster Server (non-shared storage) with a file sharing witness. I'm testing some of the different failover scenarios to see that everything is working properly. Everything works fine until I try testing the failure of the SQL Server service. When I stop the SQL Service on the primary server, it fails over to the secondary server as expected. I then start the service on the (now) secondary server and it comes back online as the secondary server. I then try to test that the service will fail back over when I stop the service on the new primary server.
However, when I stop the service, the secondary server now shows "resolving" and never comes back online. When I bring the service back up on the primary server, the secondary now shows as secondary instead of resolving. So to see if it's something about failing over from one server to another, I do a manual failover making the original primary server the primary again and everything is as it was originally.
I then stop the service on the primary server, but the secondary server now says resolving and the AG will not become available again until I start the service on the primary server.
It seems that when I first configured the quorum it worked fine the first failover scenario, then stopped working. I then added the file sharing witness, and failover worked the first time again, but not after that. For some reason after the initial failover it won't automatically failover again after that.
Config:
Servers: Windows Server 2012 Standard
SQL : SQL Server 2012 Enterprise SP1
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.
Is it possible to ONLY allow a login to the availability group listener, but block logins to server instance/nodes?
So: MySQLServerA and MySQLServerB are in an avail group "MyAvailGroup".
I want users to login to MyAvailGroup's listener, but I do NOT want them to login to the actual hosts/nodes directly.
Is that possible?
I have a situation where I have two servers in SQL Server 2012 R2 AlwaysOn Availability Group. One is primary and the other one being secondary. I am only running SharePoint Database on it.I have run out of space on the primary server and about to run out of space at the secondary server. I have tried shrinking database transaction log files, but it returns an error that it cannot be shrunk as the database is in the AlwaysOn Availability Group.
Questions:
1. Several forums suggest that databases need to taken out of AlwaysOn Availability Group in order for the shrinking to work properply?
2. Would it have any impact on the database if it is taken out of availability group and then added back?
I Config Ha-Alwayson on 2 test servers . In addition, was defined a listener for them.i can connect to them from the listener and in directly. I did manual Failover and it worked.However all connection to all servers (primary and secondary and listener) was breaked. I expected my connection To The listener, be stable. But How can I test the Auto failover mechanism? I run this scenario :
1- I filled all free space from the primary server else a bit.
2- And run on it a Huge Update to fill remain free space.
3- MeanWhile I Run an insert command into listener IP. (in a while Loop)
I expected :
>>> After run update or in middle of it , The primary server face to a problem. (Full Log file). And This was happened.
>>> After I expected The Failover act and change Primary And Secondary.And My insert commands Continues without Break Or Continue On new server After some Seconds
But It didn't Happend.Both Of 2 Command are stoped !!!!! And auto failover didnt act. I tryed To create a manual fail on primary server . I Tried to Offline the main database in primary server.
Then
1- What is the meaning Of fail that Auto failover act about it ?
2- In which scenario I can Test It ?
In always on docs in msdn they mention only about backup of secondary.. explain the backup of primary or how logs are managed in primary database. My doubt is a normal database in full recovery mode the log file will grow if we didnt take proper log backup,how the same is managed in primary in Always On.
View 2 Replies View RelatedWe have a database in an AlwaysOn Availability Group that has gone into a state of Not Synchronizing / Suspect on the secondary.
The reason why this happened is because the secondary ran out of disk space so the log file wasn't able to be written to. The database was set to synchronous mode.
Is the only way to recover from this to do a re-initialization or is there another way to recover?
I have a 3 node 2014 AlwaysOn setup. The primary and secondary are set for automatic failover. The third node, of course, is manual (until 2016). The 2 nodes with are automatic are sitting in one datacenter, the third is in another. If the first datacenter was to go down, I would manually have to failover to the third node? What's the normal process here for having two datacenters and ensuring the availability group is always available?
View 3 Replies View Relatedwe have to build high availability SQL 2012 cluster for VDI and we have two options. One option is to build a server cluster with combination of failover and mirroring and other option is to build failover cluster with AlwaysOn.We are not sure which option to chose. We have contacted Microsoft support to provide us some documents and instructions for failovermirroring combination but they have send us instructions for AlwaysOn option.
What would be best way to build high availability cluster for VDI? Also, since first option is very complicated.
How to find when (date/time) a database was last removed from AlwaysOn Listener?
Is there any query (DMV) to find the details easily?
how to check the errors when a database is configured in Always on in sql 2012?
View 1 Replies View RelatedSecondary replica database(setup in async mode) of AlwaysON went in "restricted mode" during weekly reindex operation.
So I have tried below steps
1) Executed following statement on the same secondary replica database where the issue exists
alter database <DBNAME> set multi_user with rollback immediate
but it failed with the error saying "The operation cannot be performed on database "dbname" because it is involved in a database mirroring session or an availability group. Some operations are not allowed on a database that is participating in a database mirroring session or in an availability group. ALTER DATABASE statement failed."
2) Primary database is multi_user but still tried following command on primary replia database(thinking it will replicate)
alter database <DBNAME> set multi_user
but no luck. The secondary alwaysON database shows (synchronizing) as the alwaysON is set in async mode but the command doesn't replicate across secondary
so we are left with the only option to re-setup alwaysON but I want to avoid it as database size is huge..
any other options or am I missing anything?
MCP,MCDBA(SQL 2000),MCTS(SQL 2005),MCITP(SQL 2005)
Is there any single TSQL query which provides below info.When did my AlwaysOn Availability group failed over and from which node it failed to which new node(i.e. replica)?
View 3 Replies View RelatedI'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 am running SQL 2014 2-node AlwaysON Availability groups, Enterprise Edition in our environment and 5 databases are part of AG.
Question is, sometimes AG is getting failed over to node2 but always our preferred node is node1 due to some business needs otherwise some of our jobs will fail.
So, what I looking for is, a sql script which can handle a situation wherein, for some reason, AG is failed over to node2, it should be able to detect if node1 is back online or not and if so, it should fail back to node1. How to do this using tsql query or stored proc or sql agent job ?
We have a requirement to build SQL environment which will give us local high availability and disaster recovery to second site. We have two sites- Site A & Site B. We are planning to have two nodes at Site A and 2 nodes at Site B. All four nodes will be part of same Windows failover cluster. We will build two SQL Cluster, InstanceA will be clustered between the nodes at Site A Server and InstanceB will be clustered between the nodes at Site B, we will enable Always On Between the InstanceA and InstanceB and will be primary owner where data will be written on InstanceA and will be replicated to InstaceB. URL....Now we want we will have instanceC on the Site B and data will be writen from the application available on Site B, will be replicated to the instance on the Site A as replica.
View 6 Replies View Related