SQL Server Admin 2014 :: AlwaysOn Transaction Log Filling Up
Jul 18, 2015
I have a database that is part of AlwaysOn that is filling up the transaction log drive even though I have a daily full backup and transaction logs set for every 2 hours. The backups are going from both the primary and secondary replica backuping up to the shared disk and I have the backup preferences set to the primary.
When I try to shrink the log I get 'The transaction log for database 'DB' is full due to 'LOG_BACKUP''. I have to manually backup the trans log and then shrink, why the maintenance plan backups aren't doing this even though they are "working".
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?
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?
We had a big issue today during maintenance work in our SQL environment.
So our environment: - 2x SQL Server 2014 Enterprise on Windows Server 2012 R2 (SRV1 and SRV2) -- Both Hyper-V VMs on different Hosts -- Both configured to an Windows Failover Cluster and AlwaysOn Availability Group (AG1) -- AG Listener: AG1_lis -- No shared storage (each Hyper-V Host has its own local storage) -- Asynchronous Mode -- SRV1 is primary, SRV2 is secondary SQL node
What happened? - Shutting down Windows on SRV2 due hardware maintenance - Cluster goes offline, AG1 goes offline -- Error message: "Stopped listening on virtual network name 'AG1_lis'." -- Error message: "The availability group database "DatabaseXY" is changing roles from "PRIMARY" to "RESOLVING" because the mirroring session or availability group failed over due to role synchronization."
Results? - AG1_lis wasn't available for our applications and they stopped working properly because database connection was lost!
I think, I HOPE, this is not the normale behaviour when one node is shutting down (especially the secondary node!)
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.
I am trying to build out an AlwaysOn AG with 2 nodes each in a different subnet (in AWS if that matters), windows 2012r2 / SQL 2014 RTM
I created a AG Listener with 2 ip address, 1 for each subnet (checked that neither ip address are used). But whenever i failover the AG to the secondary, and try and connect via the listener it fails,
I am trying to connect via SSMS from the primary instance. and just time out, If i roll over to the primary i can connect no issues, I've tried playing with the connection settings, upping the time out to 30 secs, adding the MultiSubnetFailover=true. etc but not getting any joy.
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)?
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.
How you are handling the replication of the many instance-level objects/items (logins, linked servers, server roles, database mail, operators, on and on) to the replicas in an AlwaysOn topology.
I'm especially curious about DBAs managing larger SQL Server environments. In my current environment, we have approximately 80 production SQL instances containing about 650 databases that require high availability and disaster recovery.
We use mirroring today and have a solid, home-grown solution for replicating the instance-level items from production to disaster recovery. AlwaysOn changes things a bit since we'll have multiple replicas and of course the database could be active on any one of those at any time. So my concern is about instance-level items being created in one instance but never deployed to the other instances participating in the AG group.
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)?
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?
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.
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...
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.
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 ?
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?
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 ?
I have Full database backup upto previous day and transaction logfile of Today transaction. my database has crashed. I have restored previous day's Full backup. I have faced difficulty to restore today's transaction from today's transaction log. What are the steps to restore full database back and one day's transaction log file. Note: there is no differential database backup and transaction backup.
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.
Is there a formula for calculating how expensive a transaction will be in terms of disk space used before its run. I dont want it accurate to the MB, but rough enough so I can determine how much additional space to assign to a transaction log or SAN volume.
Currently we're reindexing ~25billion rows, nothing too wide, say 12 columns consisting of 1 varchar(50) and the rest ints, bits and money.Roughly speaking if I reindex the clustered index on an int indetity, (with sort_in_tempdb) how would I calculate the the disk space used?
We have multiple databases on a single instance in an OLTP environment. I have my data files on a separate SAN LUN from my transaction log files (and a few NDFs split out onto additional LUNs). I was wondering if there is a performance benefit to putting each LDF file on its own LUN? Or at least my few busiest LDFs?
We are currently on 2012, but I'm having to put together specs for a 2014 installation and need to answer this question without having an environment in which I can benchmark different setups. I just want to hear whether or not others have done this (why or why not?).
I'm working on a large scale project that is currently in production. We have a big process that recently changed to use In-Memory Tables with SQL 2014 for performance efficiency.
The Process uses:
51 In-Memory SQL Tables. 50 Stored Procedures (not native) that loads data(Insert) from about 150 regular Tables and IM tables. 300 Validations (short stored procedure not native) Selecting from those 50 In-Memory Tables (And insert to In-Memory table that save the validation errors if exists on In-Memory table).
At the end of this process we clean the table from the data that relavnt to etch prosses(DELETE FROM WHERE)
B.T.W No UPDATE STAT on In-Memory are used-when we test the prosses it slow as down and cause some locks.
We are calling this process from ADO.Net, loads stored procedure first and then validations, each SP use different SQL Connection. In normal use, everything works fine and takes about 1.5 second.
Under stress test (6 Clients X 100 Tasks) for 30 minutes. After several minutes we are starting to get this SQL Exception (1 SQL Exception for every 20 tasks):
41301. A previous transaction that the current transaction took a dependency on has aborted, and the current transaction can no longer commit.
Transactions in Memory-Optimized Tables
The Exception is not clear. We are not using BEGIN TRANSACTION in the process. The SQL Exception occurs in different stored procedures each time.
I've recently started working with a public sector organisation who have 4 clustered sql instances that has 80% of it's db mirrored.
Looking at the transaction log - it seems that a transaction log backup is a good idea as the log is 4x larger than the data file.But I'm not allowed access to the physical server to check onto which drive I can create the trn. No RDP, no vmware - let's be honest I'm not even allowed to launch cmd line Also the Server Manager informs me "We will need to carefully look at database backups if you guys want to start doing these backups on box, as that will break our off box backup routine (it will screw the transaction chain)."
I don't understand how backing up the transaction log could break the "transaction chain"?
