How Database Mirroring Can Repair Page Corruptions
Aug 29, 2013
If we restore a database (full backup) first and continuously apply its transnational log backups, do we end up with two identical databases at page level eventually?
If so, page level repair to principle server may work as documented. I can see SAN level mirroring will give you exactly two identical databases at page level eventually at some point of time.
I can see Sybase device (in MS word file) level mirroring will give you two identical things at page level for same device.
But applying the transcriptional logs sequentially on the other servers, can SQL Server guarantee these two databases are identical at page level given there is server configuration can be different?
I have SQL Server Enterprise set up with Merge replication, it is being used to Sync with Windows Mobile Devices as the subscribers.
All the Windows Mobile subscribers have been synchronising fine up until recently, when 1 of the Subscribing Windows Mobile devices received this error. The day after, another device Synchronised fine the first time (note that the Synchronisation was a long one and the SDF grew in size dramatically while the synchronisation occured, but the Sync worked fine and the SDF dropped back to its initial size) The 2nd sync 5 mins later failed however so this Mobile device has the same error also.
Any suggestions as to the below are much appreciated
a) Why this error occurs? b)How do you resolve this error? c)What is the Repair utility mentioned in the error, and is it of use to me?
Thanks in advance, I am very greatful for any advice.
I have inherited a poorly administered/maintained database thatcontains the following error:"I/O error (torn page) detected during read at offset 0x000018ee23e000in file 'F:Program FilesISSRealSecure SiteProtectorSiteDatabaseDataRealSecureDB.mdf"I do not have database backups and so therefore cannot restore fromthem. I want to move the database to a new platform and somehowrepair the torn page. Is this possible?
I got help from Dan Guzman on how to set single-user-mode.Thank you very much.After seting single-user-mode, I run DBCC CHECKDB('MYDATABASE',REPAIR_REBUILD)Tehre are error messages.How can I repair torn page problem?Thanks.*** Sent via Developersdex http://www.developersdex.com ***Don't just participate in USENET...get rewarded for it!
I have a corrupt .sdf database sat on a SD Card but i am unable to find a way to repair it.
So far I have tried a few different methods, most of which just tell me what i already know i.e. "the database is corrupt and needs repairing!!"
I am unable to open the file in SSMS object browser (see above message) which means i cant run repair / shrink utilites. I am also unable to add the database to a vs2005 project (again see above message) meaning again i can't run any repair utilities.
I have also tried using the compact / Repair utility in Query analyser 3.0 on my Windows Mobile 5.0 PDA but once again i am greeted with an "error reading file - Run the Repair Utility" Message.
Lastly i've tried using the SQLCEengine.repair method and, depending on whether i do it on the PDA or on a desktop pc it throws the exceptions "Error occurred reading database file - run the repair utility"(PDA) or "invalid database type" (PC)
Can anyone shed any light as to whether there is another (easier???) way of doing this or if i just have to face it that this file is lost?
Thanks
ps. the code i used for the .repair is as below:
Dim conn As SqlCeEngine
Dim strdb As String
strdb = "SD CardPathnameDatabase.sdf"
conn = New SqlCeEngine(String.Format("Data Source={0}", strdb))
I started getting errors everytime i try to access my webmail(horde), my zencart and my forum so i asked my website host and they say i need to repair the SQL database. I have no idea what this means, can someone help please?
The errors are:
Horde: A fatal error has occurred Could not connect to database for SQL SessionHandler. Details have been logged for the administrator.
Zencart: 0 DB_ERROR_NOT_CONNECTED in: [db_cache table] If you were entering information, press the BACK button in your browser and re-check the information you had entered to be sure you left no blank fields.
SMF Forum: Connection Problems Sorry, SMF was unable to connect to the database. This may be caused by the server being busy. Please try again later.
I am backing up SQL 6.5 DB using Backup Exec 7.2 on NT 4.0 server SP4 with SQL server agent. The backup job ends in Failed status and a warning that DBname is corrupt. I then try to run DBCC Checkdb, newalloc, and checkcatalog commands to repair the DB. No further ahead yet. Are there any other commands that I can perform on the DB so that the corruption can be repaired, or verified there indeed is corruption of DB?
I'm an Access man moving towards SQL Server and I'm interested in knowing if there is a utility for my SQL Server version 7 database that is similar to Access' Compact and Repair utility? I'd like a recommendation from a guru on what Prevenatative Maintenance measures I should be running daily/weekly/monthly etc...
yes,I have an error, like 'The database file may be corrupted. Run the repair utility to check the database file. [ Database name = SDMMC Storage Cardwinpos_2005WINPOS2005.sdf ]' .I develope a program for Pocket Pcs and this program's database sometimes corrupt.what can i do?please help me
Running SQL 7, Standard version. I had a database marked 'suspect'. I copied the MDF and LDF files to another directory, then deleted the suspect database. I tried to create a new database and attach the MDF file to it. It did not work. Any other ideas? I have no other backups of the data. I am willing to pay for consulting over the phone if necessary.
How can I repair the database (5 gb) and remove the transaction log (45 gb). Whenever I run the maintanence wizard, it corrupts the db and I have to restore the db. Whenever I try to shrink the transaction log, the query runs but it doesn't shrink it at all. Is there a manual method for either of these and if so, how?
I support many uncontrolled MSDE installs on Win98 machines who are moving to XP. Unfortunately, many of the machine owners are choosing to upgrade their machines to XP, rather than choosing to re-roll.
The problem with this is that the edition of MSDE 2 (SP2) that I'm supporting not only gets it's registry items for the services ripped out, but the perflib registry itself becomes truncated by the MS Windows upgrade. So, no services and the thing can't be uninstalled due to performance monitor rollback issues...
Refer you all to MS KB Article 300956 and the fix for the broken registry which includes expanding system files that contain the default perflib entries referenced by registry. I ran through this process and found that it worked. I was then able to install a named instance of MSDE and remove the broken copy, followed by the instance. From here an install of MSDE went on fine. So what am I posting for?
Adding performance counters into the perflib/009 registry key during the install (which is a condition of my MSDE install and can't be changed) is all well and good, but what about other applications requiring performance counters? Since they have been replaced by the system default performance monitors what kinds of other services, apps or anything may be adversly affected? Not really a db question but directly linked to being able to support MSDE... Is there anyone out there who's had to utilise this fix before and are there any repercussions that are considered unnaceptable in terms of losing machine functionality???
Basically I need to know if taking performance counters back to the stock system settings is not all that horrible a thing to do to XP client machines, especially as the perflib keys are so corrupted anyway.
ANY THOUGHTS???
(other than formatting and starting again of course!)
Long time ago, I downloaded the Northwind and pubs databases from the Microsoft website (I do not remember the details of it) and installed these two databases together into the SQL Server Management Studio Express of my PC (Microsoft Windows XP Pro). I tried to learn an example of using "User Instance" (source code was from a book) on the Northwind database located in my SQL Server Management Studio Express. I just find out that my Northwind database has the title only and no tables at all. If I click on the "+" in front of the "Northwind", I got the following error message:
Microsoft SQL Server Management Studio Express
Failed to retrieve data for this request.(Microsoft SqlServer.Express.SmoEnum)
Additional information:
One or more files do not match the primary file of the database. If you are attempting to attach a database, retry the operation with the correct files. If this is an existing database, the file may be corrupted and should be restored from backup. (Microsoft SQL Server, Error: 5173)..
Please help and tell me how I can repair this Northwind database in my SQL Server Management Studio Express.
Scott Chang
P. S.
I deleted the name 'Northwind' in my SQL Server Management Studio Express, executed the "SQL2005DBScriptsInstnwind" program and I got the following error message: Msg 1802, Level 16, State 4, Line 1
CREATE DATABASE failed. Some file name listed could not be created. Checked related errors.
Msg 5170, Level 16, state 1, Line 1
Cannot create file 'c:Program FilesMicrosoft SQL ServerMSSQL.1DATAorthwindorthwind.ldf' because it already exist. Change the file path or the file name, and retry the operation.
Msg 15100, Level 16, State 1, Procedure sp_dboption, Line 64
The database 'Northwind' does not exist. Use sp_helpdb to show available database.
Msg 911, Level 16, State 1, Line 1
Could not locate entry in sysdatabases for database 'Northwind'. No entry found with that name. Make sure that name is entered correctly
Using SQL Server 2008, we would like propose mirroring between two servers of a critical database. Since we initiate, may require to clarify on its purpose and also required changes from application end.Any changes required from OS Level? (I believe both servers IP or Host name should be added in host entries. Mirroring ports should be allowed/open including Principal and mirror server IP Addresses): Windows Team.Any changes required from Application? (Instance name, authentication: user name and its password should be added in web config files): Application Team.Any changes required from Network Team?Also for mirroring both the principal and mirror servers should be with same version, does it only mean SQL Server 2008 versions are enough or does it also mean to say build numbers 10.00.4000 should also be same.URL....
I have just finished configuring my first test mirrored environment (High safety mode). I setup the database engine service accounts on each of the servers with domainuser. I inherited a production mirrored environment set up by someone else. On the production servers the database engine service account is NT Authorityuser a local account. I am trying to practice installing Windows updates within a mirrored environment and I not sure how to proceed when the service account is NT Authority user account. should I change the service account to a domainuser?
ALTER DATABASE foo set PARTNER = 'TCP://10.3.3.1:1234' I get this error message:
The database is being closed before database mirroring is fully initialized. The ALTER DATABASE command failed. What does that mean, and how do I fix it?
I set up a new mirror server. Everything is good except that the Database Mirroring Monitor is not working for one of the databases. In the monitor the principal data is showing up as blank
If I look at dbm_monitor_data on the principal most of the data columns (e.g. Send_queue_size) are null where as they have data for the other databases.
Both servers are SQL Server 9.0.2047 Enterprise Edition.
I have read on the web that high protection mode not recommended, except in the event of replacing the existing witness server. But I can't find the reason why anywhere. Can anybody explain? Thanks.
1. Once the mirroring is setup is it possible to switch between high-protection and high-performance modes? If it is will I have to stop the mirroring, switch the modes and then restart it again?
2. Let's say the principal server went down and I manually failed over to the mirror server. Mirror server runs as a new principal server for a couple of days and then I bring the original principal server back up. What needs to be done in order to bring transactions on the principal server up to date?
for a database mirroring , which stretergy is good. Creating with witness server or without it.?
I am firsttime doing this , so i am posting it to the forum..
and also if we are creating the database mirroring with witness server for automatic failover , will the witness server need the same amount of harddisk space like the pricipal or mirror server.??
we want to migrate our production server , without taking the database down.so what we did was , we mirrored the databases from production to one of our development servers and we took the prodcution server for uprgrade.
so today we are moving back (mirroring) all the databases from that development server to our new production server.
my question is , when i move
productionserver_old(principal server) - having the script for principal server
development server(mirror server---->principalserver)) - having the script for mirror server , which is now acting as principal server
new production server(mirror server) - having the script for mirror server. will become principal server , once i moved all the databases
now while mirroring between the developement server and the new production server, i have to run the scripts for the mirror server only.
so both the servers are havign the mirror script now...
is that a problem, or any other way i can handle this....
Does anybody know any good Tutorials for Database Mirroring (Automatic Failover) or Manual Sync with Mirror Server. I tried some sites online, but doesn't have detailed steps.. pls.help as i need to sync data with One of my Mirror using Sql Server 2005.
I have some questions about database mirroring. we have almost 40 databases in one server. Can I set up the database mirroring for all the databases. Is it going to any affect on performance. we have already setup the mirroring on almost 30 databases, and I need to set up for the rest of 10. please some body could help on this. Thank you.
Hi, i'm a novice of sql server and I have a problem. I have to reply a server in which there are database that are managed with sql server 2000 sp3; what I must make in order to set up the mirroring between the database of the two server so that the data are always aligned ?
I am new user of SQl and preparing the exam database mirroring....can you tell me how i start the mirroirng ..what is my first tep..and is there only one instance
1. Once the mirroring is setup is it possible to switch between high-protection and high-performance modes? If it is will I have to stop the mirroring, switch the modes and then restart it again?
2. Let's say the principal server went down and I manually failed over to the mirror server. Mirror server runs as a new principal server for a couple of days and then I bring the original principal server back up. What needs to be done in order to bring transactions on the principal server up to date?
