MADHU@MICROSOFT BLOG : MSDTC

HOW TO CHANGE MSDTC SETTINGS PROGRAMMATICALLY

madhu_ponduru@hotmail.com — Tue, 18 Apr 2006 03:02:00 GMT

COPY FOLLOWING SCRIPT TO NOTEPAD AND SAVE IT AS .VBS FILE

'Read all settings from comamnd window
'This script takes 4 params,1 st param=networkDtc,2nd param=DtcAuthenticationMode
'3rd param=EnablexaTransactions,4 th param=Restart DTC

EnableNetworkDTC = WScript.Arguments.Item(0)
DtcAuthenticationMode = WScript.Arguments.Item(1)
EnablexaTransactions=WScript.Arguments.Item(2)
RestartDtc=WScript.Arguments.Item(3)

'create global object

Set objShell = WScript.CreateObject("WScript.Shell")

'If Network DTC is enabled

If EnableNetworkDTC = 1 Then

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\NetworkDtcAccess", 1, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\NetworkDtcAccessInbound", 1, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\NetworkDtcAccessOutbound", 1, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\NetworkDtcAccessTransactions", 1, "REG_DWORD"

ElseIf EnableNetworkDTC = 0 Then

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\NetworkDtcAccess", 0, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\NetworkDtcAccessInbound", 0, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\NetworkDtcAccessOutbound", 0, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\NetworkDtcAccessTransactions", 0, "REG_DWORD"

End If

'Mutual authentication

If DtcAuthenticationMode = 0 Then

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\AllowOnlySecureRpcCalls", 1, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\FallbackToUnsecureRPCIfNecessary", 0, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\TurnOffRpcSecurity", 0, "REG_DWORD"

'Incoming Authentication

ElseIf DtcAuthenticationMode = 1 Then

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\AllowOnlySecureRpcCalls", 0, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\FallbackToUnsecureRPCIfNecessary", 1, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\TurnOffRpcSecurity", 0, "REG_DWORD"

'No authentication

ElseIf DtcAuthenticationMode = 2 Then

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\AllowOnlySecureRpcCalls", 0, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\FallbackToUnsecureRPCIfNecessary", 0, "REG_DWORD"

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\TurnOffRpcSecurity", 1, "REG_DWORD"

End If

'ENable Xa transactions

if EnablexaTransactions=0 then

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\XaTransactions", 0, "REG_DWORD"

ElseIf EnablexaTransactions = 1 then

objShell.RegWrite "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\Security\XaTransactions", 1, "REG_DWORD"

End if

'restart MSDTC

objShell.Run("net stop msdtc"),1,True
objShell.Run("net start msdtc"),1,True

How to implement Resource Manager in SYSTX?

madhu_ponduru@hotmail.com — Wed, 05 Apr 2006 18:10:00 GMT

Following links will help you to write resource manager by using SYSTX classes

http://msdn2.microsoft.com/en-us/library/ms229975(VS.80).aspx

http://weblogs.asp.net/pgielens/archive/2005/02/19/376609.aspx

http://blogs.msdn.com/florinlazar/archive/2005/05/17/418595.aspx

http://pluralsight.com/blogs/jimjohn/archive/2006/01/24/18280.aspx

http://pluralsight.com/blogs/jimjohn/archive/2006/01/21/18170.aspx

http://www.developer.com/net/net/article.php/3565196

SAMPLE:How to use system.transaction to intiate transaction with oracle

madhu_ponduru@hotmail.com — Tue, 14 Mar 2006 03:38:00 GMT

//copy following program into console app and replace connection string and query string

using System;
using System.Collections.Generic;
using System.Text;
using System.Transactions;
using System.Data;
using System.Data.SqlClient;
using System.Data.OleDb;

namespace TransClient
{
    class Program
    {

       static void Main(string[] args)
       {
           ConnectToOracle();
           Console.WriteLine("Press any key to quit");
           Console.ReadKey();

       }

        //Try to connect to oracle database

        public static void ConnectToOracle()
        {

         /*
          VERSION: windows xp,sp2/.NET 2.0/oracle client 9i/Microsoft oledb provider/oracle oledb provider

NOTE:

            incase if data provider can't understand systx,provide COM+/ES context
              TransactionOptions to = new TransactionOptions();
               using (TransactionScope ts = new TransactionScope(TransactionScopeOption.Required,to,EnterpriseServicesInteropOption.Full))

        */

            //using Microsoft oledb provider

using (TransactionScope ts = new TransactionScope(TransactionScopeOption.Required))
{

                OleDbConnection conn = new OleDbConnection();
    conn.ConnectionString = "Provider=MSDAORA.1;User ID=XXX;password=XXX;Data Source=oracleservername;Persist Security
    Info=False";
                conn.Open();

          OleDbCommand cmd = new OleDbCommand("insert into XXX values('5')", conn);
                cmd.ExecuteNonQuery
                ts.Complete();
            }

            //using oracle oledb provider

using (TransactionScope ts = new TransactionScope(TransactionScopeOption.Required))
{

                OleDbConnection conn = new OleDbConnection();
                conn.ConnectionString = "Provider=ORAOLEDB.ORACLE.1;User ID=XXX;password=XXX;Data Source=oracleservername;Persist
                Security Info=False";
                conn.Open();
                OleDbCommand cmd = new OleDbCommand("insert into XXX values('5')", conn);
                cmd.ExecuteNonQuery();
                ts.Complete();
            }

}

}
}

Forum Dedicated to Transactions on microsoft.com(MSDTC/SYSTEM.TRANSACTIONS)

madhu_ponduru@hotmail.com — Mon, 13 Mar 2006 18:01:00 GMT

If you have any questions about MSDTC/System.transactions,please send your question to this forum

Forum Dedicated to Transactions on microsoft.com

http://forums.microsoft.com/MSDN/ShowForum.aspx?ForumID=388&SiteID=1

How to configure DTC to support oracle transactions

madhu_ponduru@hotmail.com — Sat, 25 Feb 2006 22:08:00 GMT

(1)Make sure you have MDAC 2.6, sp2 higher and make sure you have oracle client (we have lot of problems with oracle 8i client,We recommend to use oracle client 9i or higher)

((2)Make sure Network service account has read access to oracle client dlls.

http://support.microsoft.com/default.aspx?scid=kb;en-us;816633

(2)Enable Xa transactions in MSDTC

http://support.microsoft.com/?id=817066

(3)Make sure xadll, mtxoci value is set to mtxoci.dll

Key name HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\XADLL

MTXOCI=C:\WINDOWS\system32\mtxoci.dll

(4)

Update Oracle Client software registry keys.

If you use Oracle 8.1.7 or 9i Client software, modify the values of the following registry keys to make sure they match those that are specified as follows:

Client (windows 2003/Windowx xp/windows 2000)

For 8.1.7:

=========

[HKEY_LOCAL_MACHINE\SOFTWARE

\Microsoft\MSDTC\MTxOCI]

"OracleXaLib"="oraclient8.dll"

"OracleSqlLib"="orasql8.dll"

"OracleOciLib"="oci.dll"

For 9i:

======

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSDTC\MTxOCI]

"OracleXaLib"="oraclient9.dll"

"OracleSqlLib"="orasql9.dll"

"OracleOciLib"="oci.dll"

How to test:

===========

(1)Make sure you are able to run simple query with oracle (without using any transactions)

(2)Make sure you enabled xa option in DTC and configure all oracle client settings like we discussed above

(3)If you want trouble shoot more, you can enable mtxoci trace to trouble shoot MSDTC/oracle problems

http://support.microsoft.com/default.aspx?scid=kb;en-us;301293

More info:

=========

http://support.microsoft.com/kb/244661/en-us

http://support.microsoft.com/kb/264012/en-us

http://support.microsoft.com/kb/193893/en-us

MSDTC security model in windows 2003,sp1(same as windows xp,sp2)

madhu_ponduru@hotmail.com — Sat, 17 Dec 2005 04:17:00 GMT

//This content applies to windows 2003,sp1 and windows xp,sp2 machines

Microsoft introduced MSDTC security in windows xp and windows 2003,If you didn't configure MSDTC security settings properly,you may not able to run MSDTC transactions between two machines.

like i explained in my previous blog (http://blogs.msdn.com/madhuponduru/archive/2005/12/03/499781.aspx), MSDTC is RPC application,so MSDTC security model also some what looks like RPC security model.

If you want to run MSDTC transactions between two machines,make sure you enabled "Network dtc","Allow inbound" and "Allow outbound" settings on both machines(You can configure these settings from COM+ MMC)

MSDTC has three security options

No authentication:
==================
it won't authenticate incoming user,so if you have two machines in different domain or if these machines are in different work groups or one of this machine is windows 2000,you have to choose this option

Incoming caller security:
========================

This is default security model for cluster machines,If you are dealing with cluster machines,This is the maximum security you can set.

Mutual authentication:
======================

If you are running transactions between two windows 2003,sp1 machines or if you are running transactions between two windows xp,sp2 or between windows 2003,sp1 and windows xp,sp2 and If they are in same domain.You can use this option

we documented about all these options in this KB article

New functionality in the Distributed Transaction Coordinator service in Windows Server 2003 Service Pack 1 and in Windows XP Service Pack 2

http://support.microsoft.com/?kbid=899191

http://blogs.msdn.com/florinlazar/archive/2004/06/18/159127.aspx

RPC Security Essentials
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/rpc/rpc/rpc_security_essentials.asp

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/rpc/rpc/rpcbindingsetauthinfoex.asp

How to change System.Transactions timeout?

madhu_ponduru@hotmail.com — Fri, 16 Dec 2005 21:05:00 GMT

System.Transactions actually has two timeout values that can be specified in the configuration files.

In app.config, there is a “timeout” setting. If this setting is not specified, it defaults to 1 minute. But it can be overridden in code in the constructor for CommittableTransaction or TransactionScope.

In machine.config, there is a “maximum timeout” setting. If this setting is not specified, it defaults to 10 minutes. It cannot be overridden in code. It is designed to be used by the System Administrator to limit transaction timeouts. If the app.config timeout or the timeout specified in the constructors above exceed the maximum timeout in the machine.config, the timeout is adjusted down to the maximum timeout value.

How to change timeout value?

The default timeout for System.Transactions transactions is 1 minute. You can set it in either app config, web config, or machine config. Setting the default timeout looks like the following.

<configuration>

<system.transactions>

<defaultSettings timeout="00:00:30" />

</system.transactions>

</configuration>

For System.Transactions there is also a maximum transaction timeout. That can be specified only in machine config. To change that you would specify the maxTimeout property of the machine settings section.

<configuration>

<system.transactions>

<machineSettings maxTimeout="00:00:30" />

</system.transactions>

</configuration>

REFERENCE:

http://msdn2.microsoft.com/en-us/library/system.transactions.configuration.defaultsettingssection.aspx

http://msdn2.microsoft.com/en-us/library/system.transactions.configuration.machinesettingssection.aspx

Key words: Transactions MSDTC timeout System.transactions

Transaction specifications(OLE/XA/TIP/WS-Coordination, WS-AtomicTransaction and WS-BusinessActivity)

madhu_ponduru@hotmail.com — Mon, 05 Dec 2005 09:58:00 GMT

The WS specifications related to Transactions (WS-Coordination, WS-AtomicTransaction and WS-BusinessActivity) http://msdn.microsoft.com/webservices/webservices/understanding/specs/default.aspx?pull=/library/en-us/dnglobspec/html/wsatspecindex.asp.

XA transaction specification

http://www.opengroup.org/onlinepubs/009680699/toc.pdf

TIP transactions specification

http://www.ietf.org/rfc/rfc2371.txt

OLE Transactions Model
http://windowssdk.msdn.microsoft.com/library/en-us/Mts/rmguidetug_7pd8.asp?frame=true

MSDTC RPC COMMUNICATION

madhu_ponduru@hotmail.com — Sat, 03 Dec 2005 22:46:00 GMT

MSDTC is RPC application, so if you are running transaction between two machines, MSDTC will use RPC protocol to communicate with remote machine

RPC is heart of all Microsoft Distributed application (not in web service world),MSDTC,COM,COM+ will use RPC protocol to communicate with remote machine.

It is very easy to understand RPC basics, the way we did in C++, define the interface and server will implement this interface, client will use this Interface to reach remote server, in RPC world, they generate proxy/stub from this interface, and RPC will use proxy/stub to exchange data between client and server.

Any application (console/windows service) can be RPC application, they have to follow certain guide lines, you can know more about RPC here

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/rpc/rpc/tutorial.asp

HOW TO MONITOR MSDTC COMMUNICATION:

=================================

(2)You can use Microsoft Network monitor or ethereal(http://www.ethereal.com) to monitor MSDTC traffic between two machines (once you got network trace, filter it by RPC or DCERPC)

(3)to reach remote machine,MSDTC will use NETBIOS to resolve remote machine name (This means you should be able to resolve remote machine name by NEBIOS name(Just resolving remote machine name by fully qualified name is not enough)

(4)so now we know MSDTC is windows service and it will use RPC protocol and it will use NETBIOS to resolve remote machine names.

(5)If you are not able to run Transactions between two machines, first make sure Name resolution, RPC communication is working between two machines

Name resolution:

==============

You can ping by short name (for example, my machine name is TESTMACHINE.REDMONDDOMAIN.MICROSOFT.COM), ping by TESTMACHINE(short name)

Name resolution has to work in both directions, on both machines; you should be able to resolve both machine names by NETBIOS name.

In cluster case, you should be able to resolve MSDTC/cluster virtual names from all cluster nodes and client machine.

Names and IP addresses that an MSDTC client in a cluster environment must have

http://support.microsoft.com/default.aspx?scid=KB;EN-US;q311846&

RPC COMMUNICATION:

================

If you have firewall between two machines, most likely they might have restricted number of ports, if you didn't configure these machines for RPC

Communication, RPC applications (MSDTC also RPC app) can choose any port between 1024-65000, these ports may not be in firewall range, so firewall may block RPC communication

What you have to do:

================
Please choose certain range (let’s say 5000-5020), and configure this range on both machines, and open the same range in firewall, so all RPC application will choose RPC port in this range, since firewall knows about this range, it will allow the communication

Using Distributed COM with Firewalls(DCOM also uses RPC)

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dndcom/html/msdn_dcomfirewall.asp

How to trouble shoot MSDTC firewall communication
http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q306843

If you have windows firewall (most likely on xp, sp2 and 2003, sp1), open port 135 and add MSDTC to exception list

(6)My team wrote DTCPING tool to trouble shoot name resolution/RPC communication to trouble shoot MSDTC problems

You can download DTCPING from here

http://www.microsoft.com/downloads/details.aspx?FamilyID=5e325025-4dcd-4658-a549-1d549ac17644&DisplayLang=en

This KB article also gives you instructions on how to use DTCPing.

http://support.microsoft.com/default.aspx?scid=kb;EN-US;Q306843

HOW TO RUN DTCPING:

==================

(1) Start DTCPING.exe on both machines (let say on Machine1 and Machine2)

(2) from Machine1, ping Machine2

(3)from Machine2,ping Machine1

Once you are done with test, please close DTCPING.exe on both machines, if you want to test again, close current DTCPING.exe and start dtcping.exe again on both machines

Once you got dtcping log files, look for error message, mostly it will report following problems

(1)Name resolution problem (not able to resolve remote machine name by NEBIOS name)

(2)RPC communication problem (it will show us RPC communication went ok or not)

(3)it will read all ipconfig info and MSDTC security settings on XP,2003 machines

NOTE:

=======

DTCPING is working doesn't mean that MSDTC going to work, DTCPING will test RPC communication, so if DTCPING communication working means, DTC communication also may work, because of MSDTC security, we may still see transaction problem; I will cover more about MSDTC security in next blog.

I hope, I covered enough about MSDTC RPC communication, and How to trouble shoot MSDTC rpc communication problems, if you have any questions on MSDTC rpc communications, please let me know

MSDTC BLOGS

madhu_ponduru@hotmail.com — Fri, 02 Dec 2005 23:54:00 GMT

I found these blogs are very useful to know about MSDTC(I just want save you some time,adding all the blog links here)

http://blogs.msdn.com/florinlazar/
http://pluralsight.com/blogs/jimjohn/default.aspx

http://blogs.msdn.com/esperpento/

http://blogs.msdn.com/miguel/

http://pluralsight.com/wiki/default.aspx/Don.TransactionAsks