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?
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 ?
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.
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?
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.
if for any reason AG fails over to async node, how replication behaves? As data will not be in sync with previous primary replica, how replication will work? I think that we have to reset replication from scratch as there's a high chance subscribers might be more updated than current primary replica as failover to this node causes data loss. How to keep replication in sync without resetting up? Can we achieve this?
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)?
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?
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.
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.
Hi there, I am testing the db mirroring, making sure it will auto failover. I've stopped the SQL services on my principal and then I looked at the mirror db is says it's restoring. It stayed like that for 10 min before I enabled the mirroring again. Anyone knows why it's not failing over??????
Here's my setup: SQL 2005 Standard, Server 1 Principal, Server 2 Mirror & Witness.
We've recently set up a Principle, Mirror and Witness configuration with the Mirror and Witness in a separate building to the Principle. All three are part of the same domain (DMZ) and are different servers, the buildings are connected via a fiber optic cable. All servers and SQL Server instances are logged in with the same domain admin account DMZesAdmin.
Mirroring is all set-up and the databases are synchronized. Every once in a while some (not all, normally 6 out of 15) databases will switch roles and become active on the mirror. The SQL Server mirroring monitor job then reports:
Date 25/01/2007 12:37:01 Log Job History (Database Mirroring Monitor Job)
Step ID 1 Server DMZSQL01 Job Name Database Mirroring Monitor Job Step Name Duration 00:00:02 Sql Severity 16 Sql Message ID 32038 Operator Emailed Operator Net sent Operator Paged Retries Attempted 0
Message Executed as user: DMZesadmin. An internal error has occurred in the database mirroring monitor. [SQLSTATE 42000] (Error 32038). The step failed.
I have no idea, what causes the failover, it could be a slow network or a bad set-up, can anyone give me some ideas of what to do to track down the problem or any experience of what could be causing this, it happens randomly every day or three. No warning and if I go to the mirror and failover back to the principle again then it's all just fine. However I don't want half my databases working on 1 server and half on the other.
Any ideas?
Thanks Ed
UPDATE:
I've just been looking at the logs on my Mirror and at the same time it reports in this order
Error: 1479, Severity: 16, State: 1.
The mirroring connection to "TCP://DMZSQL01.dmz.local:5022" has timed out for database "WARCMedia" after 10 seconds without a response. Check the service and network connections.
Database mirroring is inactive for database 'WARCMedia'. This is an informational message only. No user action is required.
Recovery is writing a checkpoint in database 'WARCMedia' (41). This is an informational message only. No user action is required.
The mirrored database "WARCMedia" is changing roles from "PRINCIPAL" to "MIRROR" due to Failover.
Database mirroring is inactive for database 'WARCMedia'. This is an informational message only. No user action is required.
...
This looks like a time out, is there any way to set the TimeOut threashold for Database mirroring or set retry intervals??
3 servers - PRINCIPAL IP: 10.2.5.31 - DNS Lookup: db-server-2.mosside.choruscall.com - MIRROR IP: 10.2.5.30 - DNS Lookup: sql-mirror.mosside.choruscall.com - WITNESS ip: 10.2.5.32 - DNS Lookup: sql-witness.mosside.choruscall.com
Each Server is running Windows Server 2003 Enterprise Edition with SQL Server 2005 Enterprise Edition. All server instances are enabled for remote connections(By default they are not). All servers have the flag 1400 traceon and have been restarted. PORT 5022 is unrestricted on network.
The server instances are connecting via certificates. Each server has an endpoint for the certificates to to connect on.
Certificate Setup Proceedure:
Principal_Host:
1. Create Master Key with Password
2. Create certificate with subject
3. Create endpoint for certificate (Listener_Port = 5022, Listener_ip = all) to connect on for database_mirroring
4. Backup Certificate (principal_cert.cer)
5. Take backed up certificate to Mirror_Host
(Reapeat Steps 1-5 for Witness and Mirror)
Mirror_Host: Create Certificate on Mirror_Host for inbound connections from Principal:
6.(On Mirror_Host) Create Login for Principal using same password in step 1 (principal_login)
7. Create user for login just created. (principal_user)
8. Create local certificate for Principal on Mirror using certificate generated by principal.
ex: Create Certificate Principal_cert Authorization Principal_user FROM FILE='c:principal_cert.cer'
9. (If an endpoint has been created already on the mirror)Grant connectiion to the login:
ex: Grant connect on endpoint::mirror_endpoint to principal_login
Repeat Steaps 6-9 for Principal and Witness Servers accordingly.
10. Import Database to SQL Server 2005 Principal Instance
11. Backup Database to disk with format
12. Backup Database log file to disk with format
13. Copy backups to mirror
14. Restore Database and log file with norecovery on Mirror_Host
15. Configre Database for Database Mirroring on Principal Server
There are two ways to do this. Via the wizzard or via the Transact-SQL window. Using the wizzard appears to work since I started using FQDN.
PROBLEM:
After configuration, everythig appears to be correct. That is, the principal displays that it is the principal and it is synchronized with the mirror. The mirror also displays that it is the mirror and it is synchronized with the principal and it is in recovery. If I failover manually, the mirror becomes the principal and the principal becomes the mirror (They form a quarum). If I disconnect the principal from the network, the mirror is supposed to form a quarum with the witness and promote itself to principal status. This is not what is happening. The witness recognizes that the principal is down and logs that info into its log file. The Mirror attempts to contact the witness but cannot log onto the machine. The Mirror Logs the following:
Error: 1438, Severity: 16, State: 2. The server instance Witness rejected configure request; read its error log file for more information. The reason 1451, and state 3, can be of use for diagnostics by Microsoft. This is a transient error hence retrying the request is likely to succeed. Correct the cause if any and retry.
<<<<<<<MIRROR SERVER >>>>>>>>
2007-09-06 15:08:45.32 spid23s Error: 1438, Severity: 16, State: 2. 2007-09-06 15:08:45.32 spid23s The server instance Witness rejected configure request; read its error log file for more information. The reason 1451, and state 3, can be of use for diagnostics by Microsoft. This is a transient error hence retrying the request is likely to succeed. Correct the cause if any and retry. 2007-09-06 15:09:05.32 spid23s Error: 1438, Severity: 16, State: 2. 2007-09-06 15:09:05.32 spid23s The server instance Witness rejected configure request; read its error log file for more information. The reason 1451, and state 3, can be of use for diagnostics by Microsoft. This is a transient error hence retrying the request is likely to succeed. Correct the cause if any and retry. 2007-09-06 15:09:25.33 spid23s Error: 1438, Severity: 16, State: 2. 2007-09-06 15:09:25.33 spid23s The server instance Witness rejected configure request; read its error log file for more information. The reason 1451, and state 3, can be of use for diagnostics by Microsoft. This is a transient error hence retrying the request is likely to succeed. Correct the cause if any and retry. 2007-09-06 15:09:45.34 spid23s Error: 1438, Severity: 16, State: 2. 2007-09-06 15:09:45.34 spid23s The server instance Witness rejected configure request; read its error log file for more information. The reason 1451, and state 3, can be of use for diagnostics by Microsoft. This is a transient error hence retrying the request is likely to succeed. Correct the cause if any and retry. 2007-09-06 15:10:05.35 spid23s Error: 1438, Severity: 16, State: 2. 2007-09-06 15:10:05.35 spid23s The server instance Witness rejected configure request; read its error log file for more information. The reason 1451, and state 3, can be of use for diagnostics by Microsoft. This is a transient error hence retrying the request is likely to succeed. Correct the cause if any and retry. 2007-09-06 15:10:25.36 spid23s Error: 1438, Severity: 16, State: 2.
<<<<<<< WITNESS SERVER >>>>>>>>
2007-09-06 14:19:55.90 spid52 The Database Mirroring protocol transport is now listening for connections. 2007-09-06 15:07:11.64 spid24s Error: 1479, Severity: 16, State: 1. 2007-09-06 15:07:11.64 spid24s The mirroring connection to "TCP://db-server-2:5022" has timed out for database "APS_SQL_DEV" after 10 seconds without a response. Check the service and network connections. 2007-09-06 15:07:43.20 Server Error: 1474, Severity: 16, State: 1. 2007-09-06 15:07:43.20 Server Database mirroring connection error 4 '64(The specified network name is no longer available.)' for 'TCP://db-server-2:5022'. 2007-09-06 15:08:06.03 spid9s Error: 1474, Severity: 16, State: 1. 2007-09-06 15:08:06.03 spid9s Database mirroring connection error 2 'Connection attempt failed with error: '10060(A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.)'.' for 'TCP://db-server-2:5022'.
we're running a mirrored database with High Availability for Automatic failover including a Witness instance for a web application.
When doing a manual failover on the database in Management studio, the roles are switched correctly and the database is in "Principal, Synchronized" and "Mirror, Synchronized/Restoring" mode. The web application has no problems switching servers by using client failover with the jdbc driver. There is no problem accessing the database with Management Studio.
However, if we stop the SQL service on the Principal server the role is automatically failed over to the Mirror server by the Witness. The database is then in the mode "Principal, Disconnected" which should be fine. However, accessing the database from the web application or with Management Studio yields some strange results. It is not possible to write to the database, and reading from the database works inconsistently (the web application seems like it can do it, but not from the Management Studio).
Starting the SQL service on the former Principal server makes the database go into mode "Mirror, Synchronizing/Restoring" and "Principal, Synchronizing". And it will stay that way indefinitely. There are not that many updates/transactions made to the database that can make it stay in this state, especially if you can't write to the database in the first place.
The next step taken after being stuck in this state is to stop the SQL service on the Mirror (former Principal), restart the service on the Principal (former Mirror). Accessing the database now works. The database is in mode "Principal, Disconnected". Starting the SQL service on the Mirror (former Principal) makes the database go into the normal "Principal, Synchronized" and "Mirror, Synchronized/Restoring" mode. Access to database is normal.
The same erroneous behaviour can be observed by unplugging the network cable on the Principal server, so it seems like we can only get a smooth transition by doing a manual failover.
Any ideas on what might be the problem? Has anybody experienced a similar situation?
I'd like to understand why it is not possible to automatic Failover Availability Groups using Failover Cluster Instances. I think it would be great for DR and HA. Do you understand why that limitation exists?
The link [URL] ....
SQL Server Failover Cluster Instances (FCIs) do not support automatic failover by availability groups, so any availability replica that is hosted by an FCI can only be configured for manual failover.
I have set up a 2 node availability group to take advantage of using the secondary node for a read-only replica. I actually am having two issues. The first being I can connect to the primary node using the listener dns name and ip address, but no longer can connect via its actual host name or ip address. I can ping the address with no problem, but I can't connect to port 1433 using the actual host name or ip address.
I am no problem connecting to the secondary node using its host name, but can not get to it through the listener using the applicationintent=readonly. Eventually I would like for everything to connect through the listener name, but for now still need to connect via the server's host name and don't understand why; everything I read is that the primary node should be able to be connected via both the host name and the listener name.
Our network guys have to carry out an IBM Flex Chassis move at our data centre, which will affect the primary replica of one of our SQL 2012 AlwaysOn Availability Group nodes (the secondary replica won't be affected).
They have suggested using vMotion to migrate the primary replica to another virtual host, which will result in a very brief period of network outage for the node.
I've done some reading and have seen a few potential issues regarding Stun During Page Send (SDPS) and increasing thresholds within WSFC. Unfortunately, we're not able to test this prior to the migration, so I have a few questions...
Would it be necessary to failover to the secondary replica node before performing the vMotion (and back again afterwards)?
How do I add my second (secondary) node in my AlwaysOn Availability Group, after adding my head node, and the secondary node is a virtual machine. See based on the attached file if it is the correct way?
We have 2 nodes window Server 2012 R2 and SQL Server 2012 Enterprise Version cluster setup. We can switch roles and Node to one node to another and revert back to previous node with out any issues. But we are facing when one Node is restarted. We could not restart that Node in cluster Service start in Failover cluster Manager. Error Details is displayed as below inside double code."Cluster node NODE1 could not to join the cluster because it failed to communicate over the network with any other node in the cluster. Verify the network connectivity and configuration of any network firewalls."
I checked windows firewall. windows firewall is all of in Node1, Node2, SAN and DC.I have disabled and enabled the Internal and private network of Node 1. I have validated the cluster. it is showing no error though.
Node1: Public IP: 10.10.0.11 SubNet Mask:255.255.255.0 Default Getway: 10.10.0.1 Prefered DNS: 10.10.0.10 (Ip of DNS)
[code]....
Private Network: Not configured.pinging to each other ip is successful from one node to another.
I have setup a mirror configuration with a witness to be able to use the automatic failover. The principal is DBSP01, the mirror is DBSP02 and the witness is DBSP03. I have an application running an DBCP01. When the mirroring is working, the application can connect to the database on DBSP01. I disconnect dbsp01 from the network, so that DBSP02 becomes the principal. When I try to connect the application to the database on DBSP02, the login fails. Whithout the mirroring I was able to logon to DBSP02, but as soon as it is part of the mirroring, I'm not able to connect to it anymore, whatever the state of the database is. What could be the problem? Can anybody help?
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 ?
I have a SP that runs on the primary in 18 min and 45 min on the secondary( poorly written cursor,trying to fix it).Both machines are Exactly the same.I ran them in the middle of the night when no one was on the Sec. Node as we use it for reporting.
PLE: 7,000+ AVG Disk sec/write below .01 AVG Disk sec/read below .01 CPU below 5% both machines set a max dop 4
In an sql authentication environment with an automatic failover in database mirroring how to you manage new logins which have been created on the principle since the start of mirroring? Since the master cannot be mirrored, and the mirror database cannot be read during mirroring (except as a snapshot) in order to find the missing logins, I assume that only after failover a script should run to create the new logins and then run sp_change_users_login . The qestions are:
1) should the script create a new login first and then run sp_change_users_login with option update_one , or should sp_change_users_login using option
Auto_Fix create the missing logins?
2) But what is the password of these users? is it initially NULL , as a consequence of sp_change_users_login? What about the SIDs?
3) Or should we bypass sp_change_users_login altogether and use
CREATE LOGIN <loginname> WITH PASSWORD = <password>, SID = <sid for same login on principal server>,...as described in http://blogs.msdn.com/chadboyd/archive/2007/01/05/login-failures-connecting-to-new-principal-after-failover-using-database-mirroring.aspx
4) What is the event that would trigger this script to run after the aitomatic failover ?
Is there a definitive MIcrosoft agreed apon and recommended method to tackle this?
I'm trying to do a SQL 2008 cluster installation.I installed one node and now I'm trying to add a failover cluster node.in the "add Node Rules" I get following message:
Rule Check Result...Rule "SQL Server Database Services feature state" failed.The SQL Server Database Services feature failed when it was initially installed. The feature must be removed before the current scenario can proceed.
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.
we 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.
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 a Windows 2008 R2 Always on Cluster with 3 nodes (two in the primary site and one in the DR site).
Primary Site: -Primary Site Server1 -Primary Site Server2
DR Site 1 (to be decommed): -DR Site Server1
Our company is planning on decommissioning the DR site. But before we do this, we want to add a 4th site to the cluster. Migrate the data...and then decommission the original DR Site.
Is it possible to have this configuration:
Primary Site: -Primary Site Server1 -Primary Site Server2
DR Site 1 (to be decommed): -DR Site Server1
DR Site 2 (NEW DR Site): -DR Site Server1
IF this is possible, do I simply add the new DR site to the existing cluster (same steps as adding the first DR node to the cluster when the cluster was originally configured? or are there special steps?
