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Posts Tagged ‘SSL’

Setting up SSL encryption for SQL Server using certificates – Issues, tips & tricks

Posted by Sudarshan Narasimhan on April 21, 2012


I had posted quite a lengthy post on setting up SQL Server for SSL encryption back in October. This post has frequently ranked high on page views, thanks all for the overwhelming response. Since the time, I’ve got pinged so many times on this, that I really wanted to post another blog covering what I’ve learnt during this time and answers to some common problems faced when setting up SSL Encryption for SQL Server. So, here goes…


Basics

If a certificate is provided to SQL Server and for some reason it is not valid or SQL cannot find the certificate in the store, then it generates a self-signed certificate to encrypt communication between the server and the client. This method ensures that the login packet is always encrypted. Whether the data communication is also encrypted depends on both the server and the client. In order for the client to force encryption, the certificate used by the server should be signed by a trusted certificate authority.

When loading a certificate on the SQL Server machine, you have to keep in mind what the SQL startup account is.

1. If the SQL Server is running under a specific domain account, then you need to be logged in to the machine as the same domain account and when opening MMC, choose this option to load the Certificates snap-in, before doing the import. This makes sure that the certificate goes into the Personal store of the user who is also the SQL Service account.

image

2. If the SQL Server is running under any machine account like LocalSystem, NetworkService or LocalService, then you need to choose the option “Computer Account” in the above screenshot and then import the certificate. This will ensure that the certificate is placed under the Personal store of the machine account.

Needless to say for doing both of the above, the logged-in account must be an administrator on the machine.


Issues

1. SQL Server Configuration Manager (SSCM)  – How does it pull up the certificates and why doesn’t it show my valid certificate it the list?

Usually, SQL DBA’s don’t create certificates. This is usually done by someone else in your organization who will either install Certificate Services on a server and make it a trusted authority or buy a certificate from any on the certificate providers like VeriSign, GoDaddy.com etc. So when this certificate is not shown in SQL configuration manager, you are stuck. As I mentioned in the earlier blog post you can manually load the certificate by adding the thumbprint of the certificate into the SQL registry key “Certificate” in the location HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL10.<INSTANCENAME>\MSSQLServer\SuperSocketNetLib

I always wanted to find out how SSCM shows the certificate list and why sometimes some certificates even if valid are not shown there. SSCM uses WMI infrastructure to find out the certificates which are valid to be used by SQL Server. Now there are some additional checks done here which is not done by SQLServr.exe when actually loading the certificate on service startup.

You can use the following WMI query to see a list of certificates. This will be the same output you see in the SSCM Certificate drop-down. See example below

From SSCM drop-down certificate picker

image

  • As you can see above it listed 2 certificates on my machine.

Using the WMI Query

Save the below code as sqlcerts.vbs

strComputer = "."
Set objWMIService = GetObject("winmgmts:\\" & strComputer & "\root\Microsoft\SqlServer\ComputerManagement10")
Set colItems = objWMIService.ExecQuery( _
"SELECT * FROM SecurityCertificate",,48)
For Each objItem in colItems
Wscript.Echo "———————————–"
Wscript.Echo "SecurityCertificate instance"
Wscript.Echo "———————————–"
Wscript.Echo "ExpirationDate: " & objItem.ExpirationDate
Wscript.Echo "FriendlyName: " & objItem.FriendlyName
Wscript.Echo "IssuedBy: " & objItem.IssuedBy
Wscript.Echo "IssuedTo: " & objItem.IssuedTo
Wscript.Echo "Name: " & objItem.Name
Wscript.Echo "SHA: " & objItem.SHA
Wscript.Echo "StartDate: " & objItem.StartDate
Wscript.Echo "SystemStore: " & objItem.SystemStore
Next

Run this from command prompt cscript sqlcerts.vbs and you will see the output as shown below. I see the same 2 certificates shown by SSCM. So now we know that the certificates are shown by pulling the information from the WMI class SecurityCertificate.

Note
:
If you are using using SQL 2005, in the above VBScript, replace ComputerManagement10 with ComputerManagement.

C:\Users\sudarn\Desktop>cscript certs.vbs
Microsoft (R) Windows Script Host Version 5.8
Copyright (C) Microsoft Corporation. All rights reserved.

———————————–
SecurityCertificate instance
———————————–
ExpirationDate: 30363701
FriendlyName: SUDARN2 (SQLCert)
IssuedBy: US, VA, Somewhere, MyOrg, MyOU, SUDARN2.org.company.com
IssuedTo: US, VA, Somewhere, MyOrg, MyOU, SUDARN2.org.company.com
Name: SUDARN2 (SQLCert)
SHA: 876753a93eb4310e4415a563219a41dda732c260
StartDate: 30216851
SystemStore: MY
———————————–
SecurityCertificate instance
———————————–
ExpirationDate: 31674726
FriendlyName: SCVMM_CERTIFICATE_KEY_CONTAINERSUDARN2.org.company.com
IssuedBy: SUDARN2.org.company.com
IssuedTo: SUDARN2.org.company.com
Name: SCVMM_CERTIFICATE_KEY_CONTAINERSUDARN2.org.company.com
SHA: 4ca85862a6ed93e329f68283c6d2ad1710e2c23f
StartDate: 30205010
SystemStore: MY

Part 2 of this question is why the SSCM doesn’t show your certificate. Here are some common reasons :-

  1. If yours is a clustered instance of SQL Server, then the CN in your certificate will contain the FQDN of your virtual server name of the instance and not the node names. SQL Configuration Manager does a direct match between the current machine name and the CN name in the certificate [i.e. certificates that match the machine name are only displayed], which will never match in case of a clustered instance. So you can ignore this and use the registry method to load the certificate.
  2. The certificate has expired.
  3. The Server Authentication property or the AT_KEYEXCHANGE property is not set.
  4. The Certificate is using Subject Alternate Names (SAN), which is not understood by SSCM.

 

2. Subject Alternate Names (SAN’s) and whether a certificate having SAN’s can be used by SQL Server.

Subject Alternative Names allow you to specify a list of host names to be protected by a single SSL certificate. This is useful when you want to buy 1 single certificate to secure multiple SQL Servers. Cheaper option I guess Smile. But anyways, certificates having SAN names are supported and SQL Server can use it for SSL encryption. If you provide the thumbprint value in registry, SQL Server will load this certificate. SQL Server doesn’t examine the SAN while choosing a certificate to load. I confess I hadn’t heard about SAN names before, so I tested this by creating a certificate using openssl.exe by having 2 alternate names. You can download openssl.exe for testing purposes from HERE.

1. Create a configuration file as follows. I called it cert_config.txt

distinguished_name = req_distinguished_name
x509_extensions = v3_req
prompt = no
[req_distinguished_name]
C = US
ST = VA
L = Somewhere
O = MyOrg
OU = MyOU
CN = SQLSERVER.SUDARN.COM
[v3_req]
keyUsage = keyEncipherment, dataEncipherment
extendedKeyUsage = serverAuth
subjectAltName = @alt_names
[alt_names]
DNS.1 = alternatename1
DNS.2 = alternatename2
IP.1 = 10.191.84.22
IP.2 = 10.191.84.23

The alternate names I have used are alternatename1 and alternatename2. Replace this with actual server names as applicable.

2. Once you install the tool, go to the ..\bin\openssl.exe location from command prompt and run the following command to create the certificate.

openssl.exe req -x509 -nodes -days 730 -newkey rsa:2048 -keyout C:\Users\sudarn\Desktop\cert.pem -out C:\Users\sudarn\Desktop\cert.pem -config C:\Users\sudarn\Desktop\cert_config.txt

3. Run the following command to create the PFX file

openssl.exe pkcs12 -export -out C:\Users\sudarn\Desktop\cert.pfx -in C:\Users\sudarn\Desktop\cert.pem -name "SUDARN2 (SQLCert)" -passout pass:mypassword

This will create a file called cert.pfx which can be used to install the certificate or imported using the MMC certificates snap-in.

Now that you a certificate with 2 alternate names you can see for yourself that SQL Server can load this certificate fine. Again you will see the SQL Config Manager doesn’t show this certificate. Most cases the main CN name will not match the machine name in case of SAN certificates and that’s why SSCM doesn’t show you the certificate.

Important
The SAN field in the SSL certificate is not examined by all SQL Server client drivers when they are validating the server certificate. Only fairly recent drivers examine the SAN when validating a certificate, like the following.

– SQL Server Native Client 10.5 (and higher)
– ADO.Net SqlClient 4.5
– JDBC 4.0

So, if the client application is using .Net 4.0, for example, and you try to rely on the SAN, the client application will not accept it. Keep this factor in mind when deciding to use SAN certificates or go with individual certificates for each machine.

3. I’ve setup SSL encryption but when I connect to my SQL Server, I get this error

Cannot connect to thematrix.CORP.COMPANY.COM
——————————
ADDITIONAL INFORMATION:

A connection was successfully established with the server, but then an error occurred during the pre-login handshake.
(provider: SSL Provider, error: 0 – The certificate’s CN name does not match the passed value.)
(Microsoft SQL Server, Error: -2146762481)

I was able to reproduce this issue quite easily. As you can see in the above error message, the reason the connection didn’t go through was because the certificate’s CN Name did not match the SQL Server name.

As documented in Books Online, there are 5 properties for a certificate that are mandatory to be use by SQL Server which are documented here http://msdn.microsoft.com/en-us/library/ms189067.aspx 

Here is the catch!

If your SQL Server machine is called “THEMATRIX” and you create a certificate called “MyServerName” and you provide the thumbprint of this certificate directly in the SQL server registry, SQL will load this certificate just fine. Surprised? Have a look at my repro.

1. I created a certificate using openssl.exe with the following properties.
CN = MyServerName
extendedKeyUsage = serverAuth
Valid From: 29 March 2012 21:27:39
Valid To:    29 March 2014 21:27:39

2. I loaded this certificate using the SHA1 hash value directly in the registry key "Certificate" in the following location,
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQLServer\SuperSocketNetLib

3. SQL Server successfully loaded this on restart of the service.
2012-04-03 02:52:57.100 Server       The certificate [Cert Hash(sha1) "A1A3DB2BD029B39FF9329E46B730CF8DF4BE2383"] was successfully loaded for encryption.

4. When I connected from SSMS, I get the same error as reported by my customer.
provider: SSL Provider, error: 0 – The certificate’s CN name does not match the passed value.) (Microsoft SQL Server, Error: -2146762481)

So now read the documentation again and it will make sense. What Books Online is telling you is that for a successful SSL encryption and connection, the subject Name in the certificate has to match the FQDN/Server name. In the above scenario, I deleted the certificate “MyServerName” and created a new certificate with the CN as “TheMatrix” and was able to connect successfully from SSMS.

4. Again with a new SSL encryption setup, you are faced with this error when connecting from SSMS

(provider: SSL Provider, error: 0 – The certificate chain was issued by an authority that is not trusted.)

This messages tells us that a server side certificate is used but the client could not validate the server side certificate. If your certificate is from a trusted authority but the client connection is failing with above error, do this

1) Go to SQL Configuration Manager
2) Go to SQL Native Client 10.0 Configuration > Right Click and Properties > Flags tab >
3) Set the property "Trust Server Certificate" to Yes
4) Restart the SQL Service

When the above property is set to True, SSL is used to encrypt the channel whilst bypassing walking the certificate chain to validate trust. If TrustServerCertificate is set to true and Encrypt is set to false, the channel is not encrypted. So you need to have "Force Protocol Encryption"=Yes and "Trust Server Certificate"=Yes.

5. The certificate thumbprint value in the registry is getting automatically changed whenever a failover of SQL Server is done

I must confess this was a strange issue to encounter and I saw this happening with my own eyes. Every time the SQL instance was failed over, even though the certificate was present on both the nodes, SQL was using a different self-signed certificate when starting up. I initially suspected this to be a cluster registry checkpoint issue, but after making sure that the registry value was correct on both the nodes, still on next failover some new thumbprint was getting loaded and this thumbprint value was also being placed in the registry.

There is a thumb-rule you can follow. When in doubt, use Process Monitor. So I did Smile. I collected a process monitor trace without any filters and saw this happening.

00:57:03.7155401 wmiprvse.exe 10752 RegQueryValue HKLM\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL10.A1XX02\MSSQLServer\SuperSocketNetLib\Certificate 6.0.6002.18005 SUCCESS Type: REG_SZ, Length: 82, Data: 7697654a3be60f1931ec04b37eae21af98aea1bd

00:57:03.7263934 wmiprvse.exe 10752 RegSetValue HKLM\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL10.A1XX02\MSSQLServer\SuperSocketNetLib\Certificate 6.0.6002.18005 SUCCESS Type: REG_SZ, Length: 82, Data: b8c0cf223b0efb4ca8ede15dd910400488a06631

From the above snippet you can see that wmiprvse.exe (WMI) is setting the value of the certificate to a new value. The thumbprint value is getting changed to a new value from what was there before. On further research, it was identified that this environment had System Center 2012 Configuration Manager installed and these SQL Server nodes were being managed by System Center. My colleague from the System Center team confirmed that there is a component there called “Certificate Manager” that frequently polls all the systems (ones with any roles installed) to check whether the certificate information there matches with what is stored in the System Center database (for consistency reasons). Obviously, since this is a clustered instance of SQL Server, we have edited the registry to provide the certificate value. System Center is not aware of this change, and it thinks that the certificate has been changed and puts in a request to generate a new self-signed certificate and updates the registry with the thumbprint of the new certificate. This was what was happening here. I am told System Center 2012 Service Pack 1 will have a fix for this problem. If you want confirmation, contact System Center MS Support.

6. You have configured SSL encryption for your SQL Server by manually entering the Thumbprint of a certificate, and now the SQL Service fails to start

There are many reasons for this, which you need to find out from the SQL Error log. One common problem that can happen when inputting the thumbprint into the registry when you Ctrl+C the value and paste it into the registry, some extra spaces/junk/invisible characters get copied over if you copy this from MMC. Have a look at the following KB article.

2010-04-16 18:56:31.48 Server      Error: 17182, Severity: 16, State: 1.
2010-04-16 18:56:31.48 Server      TDSSNIClient initialization failed with error 0xd, status code 0x38

SQL Server fails to start with error 17182 "TDSSNIClient initialization failed with error 0xd, status code 0x38" when server is configured to use SSL
http://support.microsoft.com/kb/2023869

 

7. You don’t see the option to export the Private Key when trying to export the certificate from one machine to another machine

This is definitely outside the realms of SQL Server. When you try to export the certificate you get to the screen where you have to choose the option to export the Private Key of the certificate, but the option is greyed out as shown below.

image

The reason the option to export the private key is greyed out is because the certificate was created without the option to export keys. There is an option during certificate creation for Server Authentication to “Mark Keys as exportable”, and you should choose this option. If you don’t, you can still export the certificate and install it on another node, but it won’t have the private key and without the private key SQL Server will not be able to load the certificate and hence cannot start.


Well folks, I’ve covered a lot of topics here. Believe me if you can follow these steps, I’m pretty confident you should have any issues before, during and after configuring SQL Server for SSL encryption. If you do happen to run into any issues, please drop in a comment on this post and I will respond back to this. Cheers!

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Posted in Security | Tagged: , , , , , , , , | 20 Comments »

To SSL or not to SSL, that is the question….

Posted by Sudarshan Narasimhan on October 22, 2011


A lot of database administrators out there would have heard of SSL (Secure Sockets Layer) and the security it offers, and thus want to configure their SQL Servers to use SSL for encryption of data on the wire. Bear in mind that SSL Encryption is very different from the built-in database encryption features like TDE. SSL is used for encrypting data transmitted across the network (on the wire) between the SQL Server and a client/application. Once configured all traffic between SQL Server and a client application is encrypted which has its advantages (secure transmission) and its disadvantages (performance impact due to the encryption and extra round-trip at connection time). SSL is a powerful feature that is a given standard of most systems and will definitely feature in a list of To-Have items if any security audit or standards are enforced in your company.

In this post I am not going to talk about what the SSL/IPSec standards, but going to focus on how to get a SSL configured for your SQL Server instance. Anyone who has setup SSL for SQL Server before might have encountered a situation where the certificate from a trusted authority does not get detected in SQL Configuration Manager. I am going to elaborate how to tackle that issue as well, so read on and stay safe!


What do you need for SSL?

Certificates! You will need to purchase/provision a certificate from a certificate authority such as VeriSign or GoDaddy.com


Pre-Requisite Reading Material

Encrypting Connections to SQL Server
http://msdn.microsoft.com/en-us/library/ms189067.aspx

How to enable SSL encryption for an instance of SQL Server by using Microsoft Management Console
http://support.microsoft.com/default.aspx?scid=kb;en-us;316898

How to Enable Channel Encryption
http://blogs.msdn.com/b/sql_protocols/archive/2005/10/04/476705.aspx

SQL Server fails to start with error 17182 "TDSSNIClient initialization failed with error 0xd, status code 0x38" when server is configured to use SSL
http://support.microsoft.com/default.aspx?scid=kb;en-US;2023869

I would highly recommend you read the above mentioned articles from MSDN and only then proceed with the steps listed below. Before going further I want to highlight a few important points from the above article regarding Certificate requirements. For SQL Server to load a SSL certificate, these are the requirements.

  1. The certificate must be in either the local computer certificate store or the current user certificate store.
  2. The current system time must be after the Valid from property of the certificate and before the Valid to property of the certificate.
  3. The certificate must be meant for server authentication. This requires the Enhanced Key Usage property of the certificate to specify Server Authentication (1.3.6.1.5.5.7.3.1).
  4. The certificate must be created by using the KeySpec option of AT_KEYEXCHANGE
  5. The Subject property of the certificate must indicate that the common name (CN) is the same as the host name or fully qualified domain name (FQDN) of the server computer. If SQL Server is running on a failover cluster, the common name must match the host name or FQDN of the virtual server and the certificates must be provisioned on all nodes in the failover cluster.

Now, these are the mandatory requirements. But how do you verify these properties are satisfied before trying to load this certificate in SQL Server. Here is where the tool CERTUTIL.exe comes in very handy. (Certutil.exe comes with Windows)

I have a certificate named SUDA24322118 which I am going to check to see if the above 5 requirements are satisfied. From an elevated command prompt, run the following: certutil -v -store "my" "SUDA24322118" >certprop.txt

Open certprop.txt in Notepad and check the following values:

Validity of the certificate (Requirement #2)

image

Certificate is created for Server Authentication (Requirement #3)

image

Key Specification Property (Requirement #4)

image

Subject Name (Requirement #5)

image

The last one is the tricky one. In my case, my machine name is SUDA24322118 and hence the subject name must be the same. Once all of the above are verified, the certificate is good to be used with SQL Server.


Wild-Card Certificates

SQL Server 2008 R2 and onwards support wildcard certificates. E.g., *.ABCXYZ.com could be the CN of a certificate. This means that the SQL Server Engine (Server side components) will allow you to load a wildcard certificate for SSL. There are some caveats you need to know regarding client-side issues, so please read the accepted wildcard examples HERE.

 

Unable to see the certificate in the drop-down list box in SQL Server Configuration Manager

If you have religiously followed all the steps till now but still unable to see/pick the certificate to load in SQL Server, then you can follow the workaround given below to use the certificate. To reproduce this issue I created 2 certificates on the same lab machine SUDA24322118 which is in a WORKGROUP.

1. Create a test certificate: I used MAKECERT.exe which is available with Windows SDK. I have Win7 SDK installed and makecert.exe is available in "C:\Program Files\Microsoft SDKs\Windows\v7.1\Bin\".

makecert -r -pe -n "CN= SUDA24322118" -b 01/01/2000 -e 01/01/2036 -eku 1.3.6.1.5.5.7.3.1 -ss my -sr localMachine -sky exchange -sp "Microsoft RSA SChannel Cryptographic Provider" -sy 12

makecert -r -pe -n "CN= SUDA24322118.bplogix.com" -b 01/01/2000 -e 01/01/2036 -eku 1.3.6.1.5.5.7.3.1 -ss my -sr localMachine -sky exchange -sp "Microsoft RSA SChannel Cryptographic Provider" -sy 12

The subject name in the 1st certificate has just the hostname of the computer whereas the second one has the FQDN. Both of them are stored in the local user store called ”my”.

2. If you open you SSCM, you see that only the 1st certificate is listed and the second one is missing.

image

Surprised? Don’t be. Both of them have the same properties and satisfied all the 5 certificate requirements. You can see the certificate if you open up mmc and add the snap-in for Certificates. When asked to chose the account, select “Computer Account” for the Local computer. Both of the above certificates will be present under Personal –> Certificates.

image

How do I get SQL Server to use the certificate with FQDN? Fortunately, there is a simple workaround for this.

3. Locate the Certificate Hash Value: We make use of certutil.exe again to get the cert hash value

certutil -store "my" "SUDA24322118"

certutil -store "my" "SUDA24322118.bplogix.com"

image

You can pipe the results of the above command to a text file and copy the hash value highlighted above. Remove all the blank spaces, trailing and leading spaces. For the sample above, the final hash value would be: 278e30a6ba1748bbabd360b9b8ad1d78e9104d87

4. Add the hash to the SQL Server instance Registry: Open up the registry (regedit) and navigate to the SQL Server instance hive. For e.g. a default instance of SQL Server 2008 R2 would be HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL10_50.MSSQLSERVER\MSSQLServer\SuperSocketNetLib\

In the above location there would be a entry called “Certificate” which would be blank by default. Paste the hash value noted in step #3 here. This associates the certificate with this hash in the local store with this instance of SQL Server. Next time, when SQL Server starts it will load this certificate.

image

5. Enable Force Encryption to “Yes” using SQL Server Configuration Manager.

image

Note: DO NOT navigate to the Certificate tab and try to make any changes there. Just ignore the certificate tab altogether since we have directly modified the registry (which is what the tool does anyway).

6. Restart the SQL Server service. Open the latest ERRORLOG and you can see that the certificate with FQDN has been loaded successfully.

2011-10-11 22:34:10.80 Server The certificate [Cert Hash(sha1) "278E30A6BA1748BBABD360B9B8AD1D78E9104D87"] was successfully loaded for encryption.

 

7. Make a test connection from Management Studio (SSMS) and verify using the value of column encrypt_option in the DMV sys.dm_exec_connections is TRUE, meaning the connection is being encrypted. For the real techies out there you can use Netmon or Wireshark to check if the network packet is actually being encrypted.

 

That’s all folks. There is more to client-side encryption using SSL which you can read about in the above mentioned MSDN articles. Stay secure & safe. I’ll be back with more SQL Server stuff…

Posted in Security | Tagged: , , , , , , , , , , | 15 Comments »

SQL Server service does not start after enabling SSL encryption

Posted by Sudarshan Narasimhan on August 3, 2011


I recently had a customer who came up to me with a SQL Service start-up issue. This issue started after they had enabled SSL encryption using a personal certificate. Now, before I begin let me confirm a couple of things :-

  1. The correct SSL certificate has been chosen in SQL Configuration Manager.
  2. The ForceEncryption flag is set to Yes.

There are some forum posts on this issue and I don’t entirely agree with the solutions proposed there, because they did not actually solve the real problem but worked around it without understanding how/why the problem occurred, and how to get a complete solution.

http://social.msdn.microsoft.com/Forums/en-US/sqlexpress/thread/b308d9c8-6aba-4b3b-9b32-f919816d1be2/

http://social.msdn.microsoft.com/Forums/en-US/sqldatabaseengine/thread/63c15cb5-0d12-4ea8-bf84-e3ea8a42a866/

I am going to be bold and say this; please do not follow the above posts since they are workarounds. Most people in enterprise environments cannot run SQL Service under the Local System account, which is what the above posts are asking you do to, yikes!!!

As always, the first place to check when a SQL Service does not start is the SQL ERRORLOG (yes, ERRORLOG and NOT the EVENTLOGS – I said 1st place).

For a complete step-by-step guide to approach SQL Service start-up issues, you can read the blog post I wrote on MSDN SQL Server FAQ –>
HERE

Here is what I found in the ERRORLOG,

2011-06-08 12:35:30.56 Server Unable to load user-specified certificate [Cert Hash(sha1) “XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX“]. The server will not accept a connection. You should verify that the certificate is correctly installed. See “Configuring Certificate for Use by SSL” in Books Online.

2011-06-08 12:35:30.59 Server Error: 17182, Severity: 16, State: 1.
2010-06-08 12:35:30.59 Server TDSSNIClient initialization failed with error 0x80092004, status code 0x80. Reason: Unable to initialize SSL support. Cannot find object or property.

2011-06-08 12:35:30.62 Server Error: 17182, Severity: 16, State: 1.
2011-06-08 12:35:30.62 Server TDSSNIClient initialization failed with error 0x80092004, status code 0x1. Reason: Initialization failed with an infrastructure error. Check for previous errors. Cannot find object or property.

So, it appears the certificate chosen for SSL encryption has some issues. Here are the things I checked next:-
1. The certificate itself is valid and has not expired (using certmgr.msc).
2. The certificate hash matched that of the certificate associated with the instance but it wasn’t loading.

The certificate appears to be fine. Well, what next?

The way SQL Server loads the certificate happens through the credentials of the SQL Server service account defined for this instance. So, I started to check what the SQLSvc account was and whether it had permissions to access the certificate. At this point I cam across this forum post for a similar issue

http://social.msdn.microsoft.com/Forums/en/sqlexpress/thread/db68b3bf-33a8-42d6-8dac-f7229a2f9cde

The solution listed there was to ensure that the SQL service account had a valid user profile on the server machine. This profile can sometimes be missing if the service account was changed to a new account, which doesn’t yet have a user profile created. You can verify the user profile on any machine by going to
My Computer –> Properties –> Advanced –> Settings (under User Profiles section).

image

Solution #1 (as applicable)

Identify the SQL service account and log on to the server machine that is running SQL Server, with the service account. During logon, Windows will create a new user profile for the service account.

Unfortunately, this wasn’t the scenario in my case. Another thing I have to caution people is regarding service account change. When changing the SQL Svc account ALWAYS ALWAYS use the SQL Server Configuration Manager, and NEVER do it through services.msc. Here are some reasons why:-

1. Permissions & ACL’s of SQL Server registry keys are done only by SSCM
2. SQL Server User Groups are updated with the new service account only by SSCM.
3. WMI namespace permissions are only set through SSCM.

So, if you changed the service account through services.msc, it is possible that the new service account does not have permissions to access the certificate. The certificate hash is stored in the following registry key. If the new service account cannot access it, then you “can” get the error above, since SQL cannot load the certificate due to insufficient privileges.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL10.SQL2008\MSSQLServer\SuperSocketNetLib\Certificate

I started to check if this was happening in my case and found that the SQL Service account was not even present in the local group SQLServerMSSQLUser$[Computer_Name]$[Instance_Name]. This confirms that the service account change wasn’t done through SQL Configuration Manager.

This means the SQL Service account does not have permissions to open the private key for the certificate. i.e. SQL Server failed to load this specific certificate due to insufficient permissions. Once we give the service account permission to read the private key, the SQL Server should start up without a problem.

Here is what I did to resolve it,

Solution #2

1. Identify the SQL service account (could be a domain account or any of the built-in accounts like LocalSystem/LocalService/NetworkService).

2. If the service account was set properly using SQL Configuration Manager, then it should have been added to the SQL Security Groups. Look for this on the local machine groups. e.g. SQLServerMSSQLUser$[Computer_Name]$[Instance_Name]

3. Open the Microsoft Management Console (MMC) by click Start -> Run, entering mmc and pressing Enter.

4. Add the Certificates snap-in by clicking File -> Add/Remove Snap-in… and double clicking the Certificates item.

Note:
Select computer account and Local computer in the two pages on the wizard that appears.
Click OK.

5. Expand Certificates (Local Computer) -> Personal -> Certificates and find the SSL certificate you imported or created.

6. Right click on the imported certificate (the one you selected in the SQL Server Configuration Manager) and click All Tasks -> Manage Private Keys.

Note:
You will only see this option for SSL certificates imported from a certifying authority. E.g. you will not see this for EFS, RDP certificates

7. Click the Add button under the Group or user names list box.

8. Enter the SQL service security group that you identified in step #2 and click OK.

You can also directly add the service account itself here, but for any future changes you need to repeat these steps to add that individual account. Instead its better to add the security group, since the service account will always be present here if account change was done using SSCM.

Now, when I started the SQL service you can double-check that the certificate is being loaded and used by looking for this entry in the errorlog. In my case, it started fine and SSL encryption was working.

Open-mouthed smile

2011-06-08 12:48:47.88 Server The certificate [Cert Hash(sha1) “XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX“] was successfully loaded for encryption.


Problem Solved!

Now, to check if the connection is actually encrypted you can use Netmon or Wireshark to check the network packet. Refer to the screenshot posted in this blog on how to do that. An easier way for DBA’s to verify this is to use the DMV sys.dm_exec_connections, look at the encrypt_option column. This DMV also tells you if the connection is using Kerberos/NTLM/SQL Authentication -> auth_scheme column has this value.

Hope this saves you some time.

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