Mirroring in SQL Server 2008 - sql-server

I'm trying to set up mirroring between two sql 2008 databases on different servers in my internal network, as a test run before doing the same thing with two live servers in different locations.
When I actually try and switch the mirroring on the target DB (with
ALTER DATABASE testdb SET PARTNER = N'TCP://myNetworkAddress:5022') I'm getting an error telling me that the server network address can not be reached or does not exist. A little research suggests this is a fairly unhelpful message that pops up due to a number of possible causes, some of which are not directly related to the server existing or otherwise.
So far I've checked and tried the following to solve this problem:
On the target server, I've verified that in SQL Configuration Manager that "Protocols for SQLEXPRESS" (my local installation is labelled SQLEXPRESS for some reason, even though querying SERVERPROPERTY('Edition') reveals that it's 64-bit Enterprise), and Client Protocols for SQL Native Client 10 all have TCP/IP enabled
I'm using a utility program called CurrPorts to verify that there is a TCP/IP port with the same number specified by the mirroring setup (5022) is open and listening on my machine. Netstat verifies that both machines are listening on this port.
I've run SELECT type_desc, port FROM sys.tcp_endpoints; and
SELECT state_desc, role FROM sys.database_mirroring_endpoints to ensure that everything is set up as it should be. The only thing that confused me was the "role" returns 1 .. not entirely sure what that means.
I've tried to prepare the DB correctly. I've taken backups of the database and the log file from the master DB and restored them on the target database with NORESTORE. I've tried turning mirroring on both while leaving them in the NORESTORE state and running an empty RESTORE ... neither seems to make much difference. Just as a test I also tried to mirror an inactive, nearly empty database that I created but that didn't work either.
I've verified that neither server is behind a firewall (they're both on the same network, although on different machines)
I've no idea where to turn next. I've seen these two troubleshooting help pages:
http://msdn.microsoft.com/en-us/library/ms189127.aspx
http://msdn.microsoft.com/en-us/library/aa337361.aspx
And as far as I can tell I've run through all the points to no avail.
One other thing I'm unsure of is the service accounts box in the wizard. For both databases I've been putting in our high-level access account name which should have full admin permissions on the database - I assumed this was the right thing to do.
I'm not sure where to turn next to try and troubleshoot this problem. Suggestions gratefully received.
Cheers,
Matt

I think that SQL Express can only act as a witness server with this SQL feature, you might get better mileage on ServerFault though.
Mike.

Your network settings might be OK. We got quite non-informative error messages in MS SQL - the problem might be an authorization issue and the server still will be saying "network address can not be reached".
By the way, how the authentication is performed? A MSSQL service (on server1) itself must be runned as a valid db user (on server2, and vice versa) in order to make the mirroring work.

Related

Connecting to SQL Server in a remote server from Access

We have a Server A and a Server B.
In Server A we have our ERPs made in Access and VBA.
In Server B we have an instance of SQL Server that needs to stay in that server.
Some Access databases need to link to some tables from that SQL Server instance and I don't want the password to be stored in the MSysObjects table, so I cannot manually link the tables checking the save the connection option.
I saved the connection string in a table with password obfuscation. With that connection string I re-link the tables on startup.
The instance is accessed through it's IP, not the name of the instance. If I use the name of the instance it doesn't work.
It works for me but not for other users except one.
The SQL Server instance has been properly configured to allow remote connections, the ports have been opened and rules added to firewall. If it wasn't properly configured it wouldn't work for me and the other user, so I'm pretty confident in that. The same with the connection string and the methods to stablish the connection in Access.
What I've tried:
Installing the SQL Native Client 11.0.
Installing a full SQL Server Express.
Configured the SQL Browser service to star automatically instead of being disabled.
Step 1 did not work for any user. Step 2 did work for one user but not for the rest. Step 3 did not had any effect. For me I had it installed in my machine since forever, so it doesn't apply.
If I try to do the same with a SQL Server instance in our LAN it works for every user, but not when the instance is in a remote server.
Note I have limited knowledge. Maybe I say something that does not make sense.
Ok, a few things:
Installing the SQL Native Client 11.0.
Ok, then you have to re-link the tables - choose the new driver. A refresh of the linked tables is NOT sufficent. And this ALSO means that each work station ALSO now must have native 11 instlled. And if you say decide to link using native 17 (a much newer odbc driver), then AGAIN YOU must install this native driver on each work station. While you can install multiple sql drivers on each workstation, the driver you used to link the tables MUST ALSO be installed and exist on each work station.
Installing a full SQL Server Express.
Why? What would installing a copy of sql server have to do with OTHER sql servers on other machines that you are attempting to connect to? You think installing sql server on a machine effects the sql server running say on amazon.com? So, this move makes no sense at all.
You are attempting to connect to some instance of sql server running on some other computer. Makes no sense nor will it help to install some copy of sql server that you not using, not connecting to, and that has zero to do with this issue.
Configured the SQL Browser service to star automatically instead of being disabled.
Where? The browser service is set to run and startup on the server and SAME machine where sql server is installed and running. So, yes, without question, those two sql servers A, and B most certainly MUST have the sql browser service running. That service is what allows the client computers to connect to that running instance of sql server. In the past, older (previous) versions of sql server would allow a default connection, but now in near all cases, you MUST ensure that the sql browser service is running on that computer that also has the database you are attempting to connect to.
it's worth to note that the instance is accessed through it's IP, not the name of the instance.
No, you likly have this incorrect. There are two part.
The server name - and then the "instance" of sql server running.
While you can swap out (not use) the server name, you STILL WILL NEED to specify the sql server instance.
So, you can use this format:
myservername\SQLEXPRESS
Or, you can replace the server with a IP address, but you STILL NEED the sql server instance. (by default, it is SQLEXPRESS - but you have to check what the instance of sql server database is).
192.168.1.30\SQLEXPRESS
So while you can use IP or server name - it is often more reliable to use the IP address, but that does NOT get you off the hook from having to specify the sql instance you connect to. Again, previous editions of sql server often allowed a "default" instance, and you did not in general have to specify the "instance", but now you do. And to be double clear, when using such a instance, that sql server needs to be running the sql browser service. (in fact, the browser service is what translates the incoming request to the given and correct instance of sql server).
I DON'T want the password to be stored in the MSysObjects table,
You don't have to, and in fact should NOT include the uid/password in your connection string. And in fact ZERO reason exists to do so.
What you do is execute a one time logon, and THEN link the tables without UID/password. This is not only a great idea, but it also means that your uid/password is not included in the connection strings, but also means users can't get at, or even by accident see/get the uid/password.
It also means that say someone where to launch a copy of access, and import the linked tables from this applcation. When they attempt to use the linked tables, they will NOT work.
So, then how do linked tables work without a password? (and this ALSO by the way saves you from having to re-link tables on startup!!!).
The way this works, is you in code execute a one time logon to the server on startup. That means you can either:
Prompt the user for their sql UID/password.
or
Have in code, the uid/password. (or perhaps in a text file y ou read on startup. You can thus hide, or encrypt or whatever for that uid/passwords.
Then in your startup code, you execute a one time logon. Once you done this, then all linked tables will now work - and work without having uid/password.
since you have two servers then you need to execute two logons, one for server A, and one for server B. But, once again, as long as the linked tables exist, then they will work.
Now, there are "longer" articles on how to use this logon idea, and then not have to include, or re-link your tables for the SQL uid/password.
The basic code to execute a logon is like this:
Function TestLogin(strCon As String) As Boolean
On Error GoTo TestError
Dim dbs As DAO.Database
Dim qdf As DAO.QueryDef
Set dbs = CurrentDb()
Set qdf = dbs.CreateQueryDef("")
qdf.connect = strCon
qdf.ReturnsRecords = False
'Any VALID SQL statement that runs on server will work below.
' this does assume user has enough rights to query built in
' system tables
qdf.sql = "SELECT 1 "
qdf.Execute
TestLogin = True
Exit Function
TestError:
TestLogin = False
Exit Function
End Function
Keep in mind, that ONCE you acheived a legal logon, then EVEN addtional logon attempts will return true.
Not usually a big deal, but this means you supply a valid connection to above, and if it logs on and works - then now all your linked tables (without uid/password) will work.
I note the above issue that ONCE you done the logon, then all 2nd or more times running the above will work (even if bad or incorrect!!! - DO NOT forget this tip!!!). (this can confuse the daylights out of a developer, since they execute logon, (or open a table). Then they test above routine with a BAD uid/passwords, and it works!!!
So, you have to EXIT access to clear out the password cache - no other way.
So, keep the above tips in mind.

Labview - SSMS database communication... How to communicate between Labview and Microsoft SQL Server on separate devices?

I am attempting to set up a communication between Labview and Microsoft SQL Server, on two separate devices, in order to send and receive information about the database from both labview to SQL Server and SQL Server to labview. However, when I reach the "Data Link Properties" menu, I get the same "unable to log in" error upon attempting to log into the server. The server name comes up, however, an error occurs once I move on to select the database on that server. Is there any solution or tutorial to this problem that can allow me to successfully communicate back and forth from labview and smss on separate devices?
I've opened up various ports to allow a connection, even disabled the firewalls on both devices. The devices are connected via an Ethernet cable and I AM able to ping the devices to each other. However, in regards to being unable to log into the server in ssms, I have created new users, adjusted the login properties, tried changing permissions, but anything I try doesn't seem to solve my issue.
Can't really help much without seeing the error or some of the code of what you are trying to do.
That being said, if you go to the menu and select Help>Find Examples... and search for database, you should see a bunch of different things related to database connections. You may find the Database Connection.vi one helpful.
More info on the Database Connectivity Toolkit in LabVIEW can be found here
I see there can be one of the 2 issues
1) Inbound/Outbound port rules not set, Remote connection to server is not allowed.
2) If the server has multiple instances then you need to provide full host name of the instance you are trying to connect.
*Please refer to the below link to configure firewall rules.
https://learn.microsoft.com/en-us/sql/sql-server/install/configure-the-windows-firewall-to-allow-sql-server-access?view=sql-server-2017

Test Oracle connectivity using sqlplus without password

I am in a unique situation where I need to test my server connectivity to Oracle databases however I do not have access to any account or password.
Reason why the connectivity needs to be tested is because many times there are multiple layers of firewalls between my servers and the database, and also particularly recently while trying to access RAC/Exadata databases we realized that doing a telnet on the "scan" IP range (which were the only range visible to me) was not enough and that there are underlying physical/virtual IPs that are actually used to connect which were blocked. If I can test connectivity I can at least confirm the database is accessible.
I thought about connecting using sqlplus test#DB, where "test" account doesn't actually exist. If I get a reply saying that incorrect username/password logon denied, then at least I know the database connectivity is working because at least it reached the database to perform authentication. But I have audit concerns (whether DBAs will think someone is trying to hack the system) and also whether there's an actual way or command to do this test.
like #OldProgrammer pointed out, this is pretty much an optimal case for tnsping from the command line
tnsping MY_SERVICE_NAME
Here's a good post showing the basic options. Oh, and I'm pretty sure the DBA's can still see the traffic if they want to.

SQL Server linked server error 7303 to Access database

I've performed multiple searches and read numerous pages and tried loads of different configurations and nothing seems to solve a nuisance problem we have. We have a SQL server (2008 R2 v10.50.4000) that has several linked servers to several different access databases on a different server. They are all set up using UNC paths and they work...for a time.
At some point, something happens and then we can no longer access the databases and the only way I have found to solve this is to restart the SQL server service, which obviously isn't ideal in a production environment. This is the exact error message we get when we try to access it:
OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "HIDDEN" returned message "The Microsoft Access database engine cannot open or write to the file '\servername\path01\path02\path03\databasename.mdb'. It is already opened exclusively by another user, or you need permission to view and write its data.".
Yet it works absolutely fine again if I restart the SQL Server service, so I know the settings are correct. I strongly suspect it has something to do with the Microsoft ACE driver because they all (the Access database linked servers) stop working at the same time - even though they all look at different files.
At this point I'm willing to try anything.

SQL Agent Job - Connection may not be configured correctly or you may not have the right permissions on this connection?

I'm getting this error when running an SSIS package through SQL Agent
Failed to acquire connection "ORACLE ADO.NET". Connection may not be configured correctly or you may not have the right permissions on this connection.
When I log on as the SQL Agent User and run the ssis package directly it is fine. When I then execute it through the SQL agent job, it fails.
I've read around extensively on this topic, and it seems a lot of the advise concerns how you are logged in, configuring of proxy accounts, etc, etc, etc, none of which has been helpful.
I am logging onto an Oracle database with an ADO.NET conncetion. The connection string is as follows (datasource, userid and password have been changed):
Data Source=DATASOURCE;User ID=userid;Password=password;Persist Security Info=True;Unicode=True;
I'm loading this from a registry setting using package configuration. To check that I am getting the correct string, I am writing it into a temporary log table. I am definately getting the string I need from the correct registry setting.
I've tested the oracle login credentials though PL/SQL developer, and it lets me login just fine.
As far as I can tell, as I'm using an explicit user name and password for the Oracle connection it just shouldn't matter who the SSIs pacakge is run as. The only point of failure that Ican see would be the reading of the information from the registry, but that seems fine.
I'm really quite baffled, I must confess, and would appreciate any help some of the splendid experts here can offer.
Many thanks,
James
Ok, tracked this one down after quite a lot of pain.
It was working fine on one environment, but not another, so I fired up Process Monitor (http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx) and ran a package through the SQL Agent job, comparing which system entities were hit on each enviroment.
On the failing environment, at the point of the bulk transfer operation, the package attempted to get the Oracle 11 client DLL, and then hung.
I knew that this was installed, and, moreoever, the DLL path was a system environment setting. After further investigation it was revealed that the server had not been rebooted since the Oracle Client install and the SQL Server Agent process had not bee recycled.
Yes, can you believe it, the old helpdesk fix "Can you reboot your computer?" worked.
Sigh!
We had issues at a client with running packages connecting to Oracle before stored on our sql server instance. The work around we found was to change the package property, protection level, to "Dont save Sensitive Data" and for security purposes, we encrypted the username and password in the package configuration that was decrypted by a udf in sql server. Of course, before you try the whole encryption part, I would recommend putting the username and password in the package configuration without encrypting the values to see if changing the protection level setting is the solution to your specific problem. I hope this helps.
I was getting this error when tnsnames.ora file did not have a valid entry for the environment

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