I am knocking together a short program mainly to try and learn some basics. I am finding an issue with this part of code:
{
MySqlConnection connection = new MySqlConnection("server=serverT;User Id=user;password=password;database=healer");
connection.Open();
MySqlDataReader reader = new MySqlCommand("SELECT version FROM version", connection).ExecuteReader();
reader.Read();
etc etc etc
}
Now when i build and run this, It works perfectly, no problems whatsoever, it connects up and i can read without any issue.. (The server is hosted online btw)
When i give out the exe/mysql.data.dll to anyone to run, they are thrown the exception of being unable to connect to any sql host.
I just cant see why I can connect, and they can't. I have tried this now on 3 other remote machines and they all fail to connect, but Mine works OK.
There are no access rules on the hosted sql database, I am allowing access from all IPs
Can anyone shed any light?
You are hard coding the connection string into your code. Your clients have a different server therefore they need a different connection string.
You need to create a form or a config file where the connection parameters are retrieved from.
Please read this:
http://msdn.microsoft.com/en-us/library/ms254494.aspx
Related
Using the basic SqlConnection code below, I have discovered that, at my workstation, I am unable to connect to our Sql Server 2017 deployment via ASP.NET C# code in any given type of Windows-based project, such as Winforms (.NET Framework or Core) or Console apps. However, this code will run without incident in any Web-based project, such as Web Forms or MVC, either using .NET Framework or Core.
protected void testConnection()
{
string con = "Server=MySqlServer;database=MyDatabase;Integrated Security=true";
using (SqlConnection cnn = new SqlConnection(con))
{
cnn.Open();
cnn.Close();
}
}
In a web project, this code runs. In a Windows project, I get this error:
System.Data.SqlClient.SqlException: '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)'
In investigating this problem, I have tried the following:
Explicitly declaring the domain on which my SQL server is found (eg. MySqlServer.domain.com). No good.
Explicitly declaring the SQL Server port number, according to the example shown on connectionstrings.com (eg. MySqlServer, 1433). We do use the standard port number, for the record. No good.
Changing the protection level of the test method (protected/private/public). No good.
Connecting to the SQL Server in PowerShell. This connection worked.
Pinging in the SQL Server in a command prompt. The server responded in 1ms consistently.
I have asked other users on this network to test this code in a Winforms project on their workstations. No one is able to reproduce my issue.
Consulted my sysadmin. He is so far not able to find any reason why I should be having this issue.
The only difference I have noticed in all of this is that, when I declare the port number, the Inner Exception returned with the error reads "Win32Exception: A non-recoverable error occurred during a database lookup". Otherwise, it simply reads "Access is Denied."
All of this tells me that the issue is obviously something peculiar to my workstation, but I have no idea what, apart from some firewall or other local security setting that the sysadmin neglected to check. Has anyone encountered this problem?
My VS 2019 installation is only one revision out of date as of this writing, 16.8.3 as opposed to 16.8.4. I am able to connect to and run TSQL code on any database I care to via SSMS. We connect using Windows Authentication. According to the results of "select ##version", our version of SQL Server is 2017, 14.0.3356.20 (x64).
Any insight is appreciated.
We fixed it by forcing Named Pipes to be enabled in SQL Server, as opposed to using the default setting.
After rebooting my Windows Server 2016 Standard (SQL Server 2016) my SSIS process that runs this query:
select * from openquery(HRMPROD, 'SELECT QUERY HERE' )
started failing with this error:
I get the same error if I try to run the query in SSMS. I have the same linked server set up on my test instance and the query is successful when I run it there. I have compared the linked server create script on both instances and it is the same.
Any idea where I should look for what is causing the connection issue on the one server but not the other?
Thank you.
Saying the answer is on the Oracle side is just like pointing fingers across the way. Let's just fix the issue here.
There is a connection string that is used from SSIS, (which you also used in SSMS) The connection string contains three main components to connect and would result in the 12154 error if any of them were incorrect:
Host
Instance name (different than Instance on Sql Server, think database name)
port
The port most likely hasn't change, neither has the database name, but the host...No, hasn't changed, but the DNS server used to connect most likely has! I would ping the host and see what returns from the SSIS and your SSMS host that you're using. I would expect it to fail. Find out what IP address the host is using and ping that - see if it returns. I'm guessing that's the change that needs to be updated or your Network folks need to fix a DNS configuration/server issue.
Hope this helps!
Kellyn
Since you are getting a response from the TNS Listener, the problem lies on the Oracle side. See Architecture of Oracle Network Services for an overview of how the Oracle networking handles things. Keep in mind that based on the error message you've reached the TNS Listener, so you only need to check things between TNS and the Oracle database... In other words, your networking and SQL Server settings are fine or you wouldn't be able to get this error message.
I would agree with above that the issue might have to do with the network. I have come across that a few times, where we can set everything up, but a firewall is blocking communication between the two servers.
Open up powershell on the new server and run a tracert to the target to see the hops and identify if is connecting across the network.
If it is, then run a test-netconnect on the specific port, to see if the port is open from the firewalls.
Cheers!
Some context: I'm setting up an environment to run some Ruby code our Lead wrote to connect to some remote Databases. I'm using Win10 and have WSL installed. I have installed SQL*Plus, docker, and Ruby, and am sure I have installed all the dependent gems (actually at this point I know for a fact its not a ruby problem). I'm using Docker to use a pre-built image of an Oracle Database, and I have populated it with data.
Obfuscated company DB information:
'Broken' DB (TNS no listener)
Username: W-WORK-DEV
Password: password
Host: host1
Port: 999
SID: W-WORK-DB.tech.company
'Working' DB (can connect just fine)
Username: C-OLD-DEV
Password: password
Host: host2
Port: 999
SID: C-OLD-DB.tech.company
Please note the names I have provided here are purely for obfuscation, they do not represent anything about age or even config. They are essentially the same, just different databases on different hosts. Also note this is a corporate company and would have a lot of base infrastructure for their internal network.
The issue I am having is that with the specific database I am working on, I cannot connect to it. I connect to the company intranet via a VPN (I work offsite) and have issues connecting to WORK-DB.tech.company, though I can connect to C-OLD-DB.tech.company. Methods I have tried to connect with:
Oracle SQL Developer
I have inputted all the correct jdbc strings and username / password. Have even asked other people to attempt to connect (at least 3 others). They can all access C-OLD-DB as well as W-WORK-DB. When using this method, I get The network adapter could not establish the connection.
Side note: I'm fairly sure I have connected to the DB just fine in the past, though I can't be certain because I'm fairly new to this team and have only accessed it once, if that.
SQL*Plus via WSL
I installed SQL*Plus because I think Ruby was accessing it in some capacity when running the script. I got to the point where the script was able to connect to my local docker Database, but when it tried to connect to the remote database, it would return TNS: no listener. I attempted this using sqlplus as well and got the same error.
Example:
sqlplus C-OLD-DEV/password#host2:999/C-OLD-DB.tech.company
This command works and connected to the DB jsut fine.
sqlplus W-WORK-DEV/password#host1:999/W-WORK-DB.tech.company
This command gave me TNS: no listener.
During my research I had found mentions about tnsnames.ora, sqlnet.ora, and listener.ora. I have found relevant files around the company intranet and attempted to use them in my own personal environment to no avail (one of the sqlnet.ora files actually stopped me from being able to connect to any) I found mention about a config/database.yml file related to ruby, but our code already has the database information set up and I seem to be getting to the same solution as the script when trying to manually connect via sqlplus.
Here are some relevant environment variables I have set up when doing these installs. I'm thinking that at some point when trying to set up my environment, I messed up some config that changed the way sqldeveloper or sql plus would connect to that database.
$ echo $ORACLE_HOME: /usr/lib/oracle/12.2/client64/
$ echo $TNS_ADMIN: /usr/lib/oracle/12.2/client64/network/admin
$ echo $LD_LIBRARY_PATH: /usr/lib/oracle/12.2/client64/lib
I hope I have provided all the information I have come across and have explained clearly what my issue is, if you have any questions feel free to comment about it so I can clear it up. Thank you for any and all your help.
So my problem ended up being a 'firewall/port' issue. In the end i found out that specific port I was connecting to was blocked, but I thought it was only on my system. Turns out the VPN I'm using was the issue blocking that port. Company has a Primary Data Center and a Secondary one, and apparently the SDC VPN was blocking that port from me. I switched to using the PDC VPN and it worked.
Are you using the 64 bit jdbc drivers?
I need to access unidata database from a server. I tried using vbscript.
Set conn = CreateObject("ADODB.Connection")
conn.Open"Provider=IBM.UniOLEDB.1;Data Source=myunidatadatasourcename;User ID=myuserid;Password=mypassword;Location=D:\info\mydatabase;"
uci.config file contains
<myunidatadatasourcename>
DBMSTYPE = UNIDATA
network = TCP/IP
service = udserver
host = xxx.xxx.xxx.xx
But I got an error
Can anyone help?
http://www.pickwiki.com/index.php/JavaSource has some good Uniobjects troubleshooting tips, though it's obviously java-centric. A couple of things to check and try are:
Make sure you can telnet to 31438 on the Unidata server. If not,
it's either not listening (run startunirpcd) or you have a firewall problem.
Try creating an ODBC connection and click the test button. The error messages are more informative.
If you have an ODBC connection, try removing the provider info. It's probably
not IBM any more, unless you have a really old client.
conn.Open"Data Source=ODBC Alias;User ID=myuserid;Password=mypassword"
Check out connectionstrings.com - it's super helpful for this kind of ODBC/OLEDB nonsense.
There's some setup involved on the Unidata side to allow SQL statements. If you want to try a quick test, point the ODBC to $UDTHOME/demo and try "SELECT CITY FROM CUSTOMER" which should run without errors.
I am developing code in Visual Basic 2010 and connecting to Sybase16 databases hosted on two servers. I am referencing Sybase iAnywhere in my project.
I use the connection string shown below
Public dbIMS As New SAConnection
dbIMS.ConnectionString="UserID=userid;Password=userpw;DatabaseName=dbname;ServerName=dbname;Host=192.000.000.000;"
Try
dbims.open()
Catch ex as Exception
strErrMsg=ex.Message.ToString
End Try
I can connect to some databases, but not others. Error message is "Database server not found" All databases are active and the service name and db filename are the same for each database. I can connect to some dbs on each server and as yet have been unable to find anything in common with the successful connections or the failed connections. I am certain the ip address is correct and the db and server names are correct.
I am looking for advice on how to diagnose my problem, and thanks in advance.