I'm running Exchange 2007 on Windows Server 2008 Standard 64-bit. It is also a second domain controller. The main domain controller and file server is Windows 2008 R2 Standard 64-bit. When this primary dc is shut off for whatever reason (maintenance, etc) the email does not flow in or out of the office. Each server is also a DNS server so both servers are listed in the DNS network connection. When this main DC is off there is still Internet connectivity on clients and the Exchange server so I can't figure out why mail flow stops working. Does this sound like a DNS issue? I'm sure you need more information, so if you need detailed notes or logs, please let me know and I will provide them. I'm pretty new to understanding the Exchange 2007 server setup. Thanks.

Hi Does DC1 share the connection in some way? Yes for me it sounds like a DNS issue What ip settings are used on server2 (exch+dc2)? dns, gateway..Jonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog: http://www.testlabs.se/blog

Exchange Server settings (DC2) 10.0.0.3 255.255.255.0 10.0.0.254 DNS: 10.0.0.7 and 10.0.0.3 DC1 10.0.0.7 255.255.255.0 10.0.0.254 DNS: 10.0.0.7 and 10.0.0.3 IPv6 is turned off on both as well as the other NICs disabled

Are both DC's also configured as Global Catalog servers? If not, they should be. Also, why not configure DC2's primary DNS server as itself? Can you give the details of Event 2080 in the Application Event Log on the Exchange server? Looking for the servers listed and what numbers follow (ex. CDG 1 7 7 1.....)Tim Harrington | MVP: Exchange | MCITP: EMA 2007/2010, MCITP: Server 2008, MCTS: OCS | Blog: http://HowDoUC.blogspot.com | Twitter: @twharrington

Hi Yes, thats a starter to point the DNS to itself on DC2 Do that and check the logs and update us on your issueJonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog: http://www.testlabs.se/blog | Follow me on twitter: jonand82

Point it to 127.0.0.1?

Yes, thats OK Update on your issue when you have changed and verified Jonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | Blog: http://www.testlabs.se/blog | Follow me on twitter: jonand82

Thanks. I will try that tonight. I have to do some other work and this way I can turn off the DC1 and see if works. Should I also remove the other DNS listed and just use the 127.0.0.1?

Are both DC's also configured as Global Catalog servers? If not, they should be. Also, why not configure DC2's primary DNS server as itself? Can you give the details of Event 2080 in the Application Event Log on the Exchange server? Looking for the servers listed and what numbers follow (ex. CDG 1 7 7 1.....) What about the other points here? Is DC2 a GC? What about Event 2080 info? I would personally leave the other server as a secondary DNS. Tim Harrington | MVP: Exchange | MCITP: EMA 2007/2010, MCITP: Server 2008, MCTS: OCS | Blog: http://HowDoUC.blogspot.com | Twitter: @twharrington

Both DCs are GC. The Exchange server's DNS IP addresses are 127.0.0.1 and 10.0.0.3. I shutdown the main DC and mailflow stopped. In the event log on the Exchange Server these errors appeared at the time the main DC was off. Log Name: Application Source: MSExchange System Attendant Mailbox Date: 1/3/2011 9:50:31 PM Event ID: 4001 Task Category: General Level: Error Keywords: Classic User: N/A Computer: Exch.DOMAIN.local Description: A transient failure has occurred. The problem may resolve itself in awhile. The service will retry in 56 seconds. Diagnostic information: Could not find any available Global Catalog in forest DOMAIN.local. Microsoft.Exchange.Data.Directory.ADTransientException: Could not find any available Global Catalog in forest DOMAIN.local. at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnection(ConnectionType connectionType, ADObjectId domain, String serverName, Int32 port, NetworkCredential credential) at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnection(ConnectionType connectionType) at Microsoft.Exchange.Data.Directory.ADSession.GetConnection(String preferredServer, Boolean isWriteOperation, Boolean isNotifyOperation, ADObjectId& rootId) at Microsoft.Exchange.Data.Directory.ADSession.GetReadConnection(String preferredServer, ADObjectId& rootId) at Microsoft.Exchange.Data.Directory.ADSession.Find(ADObjectId rootId, String optionalBaseDN, ADObjectId readId, QueryScope scope, QueryFilter filter, SortBy sortBy, Int32 maxResults, IEnumerable`1 properties, CreateObjectDelegate objectCreator, CreateObjectsDelegate arrayCreator) at Microsoft.Exchange.Data.Directory.ADSession.Find(ADObjectId rootId, QueryScope scope, QueryFilter filter, SortBy sortBy, Int32 maxResults, IEnumerable`1 properties, CreateObjectDelegate objectCtor, CreateObjectsDelegate arrayCtor) at Microsoft.Exchange.Data.Directory.ADSession.Find[TResult](ADObjectId rootId, QueryScope scope, QueryFilter filter, SortBy sortBy, Int32 maxResults, IEnumerable`1 properties) at Microsoft.Exchange.Data.Directory.Recipient.ADRecipientSession.FindByLegacyExchangeDN(String legacyExchangeDN) at Microsoft.Exchange.Servicelets.SystemAttendantMailbox.Servicelet.Work() Log Name: Application Source: MSExchange ActiveSync Date: 1/3/2011 9:51:31 PM Event ID: 1015 Task Category: Server Level: Error Keywords: Classic User: N/A Computer: Exch.xxx.local Description: Exchange ActiveSync experienced a transient error when it tried to access Active Directory information for user "XXX\jsmith". Exchange ActiveSync will try this operation again. If this event occurs infrequently, no user action is required. If this event occurs frequently, check network connectivity using PING or PingPath. You can also use the Test-ActiveSyncConnectivity cmdlet. More information: Microsoft.Exchange.Data.Directory.ADTransientException: Could not find any available Global Catalog in forest BLF.local. at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnection(ConnectionType connectionType, ADObjectId domain, String serverName, Int32 port, NetworkCredential credential) at Microsoft.Exchange.Data.Directory.ConnectionPoolManager.GetConnection(ConnectionType connectionType) at Microsoft.Exchange.Data.Directory.ADSession.GetConnection(String preferredServer, Boolean isWriteOperation, Boolean isNotifyOperation, ADObjectId& rootId) at Microsoft.Exchange.Data.Directory.ADSession.GetReadConnection(String preferredServer, ADObjectId& rootId) at Microsoft.Exchange.Data.Directory.ADSession.Find(ADObjectId rootId, String optionalBaseDN, ADObjectId readId, QueryScope scope, QueryFilter filter, SortBy sortBy, Int32 maxResults, IEnumerable`1 properties, CreateObjectDelegate objectCreator, CreateObjectsDelegate arrayCreator) at Microsoft.Exchange.Data.Directory.ADSession.Find(ADObjectId rootId, QueryScope scope, QueryFilter filter, SortBy sortBy, Int32 maxResults, IEnumerable`1 properties, CreateObjectDelegate objectCtor, CreateObjectsDelegate arrayCtor) at Microsoft.Exchange.Data.Directory.ADSession.Find[TResult](ADObjectId rootId, QueryScope scope, QueryFilter filter, SortBy sortBy, Int32 maxResults, IEnumerable`1 properties) at Microsoft.Exchange.Data.Directory.Recipient.ADRecipientSession.FindByANR(String anrMatch, Int32 maxResults, SortBy sortBy) at Microsoft.Exchange.AirSync.GalSearchProvider.Execute() at Microsoft.Exchange.AirSync.SearchCommand.Execute() at Microsoft.Exchange.AirSync.Command.WorkerThread() I restarted the server and then certain Exchange Services (System Attendant, Information Store) were stuck on Stopping. I had to shutdown the server again (power off) and everything started except Information Store which I had to start manually which is another question why it does that.

Have you waited at least 15 minutes after the DC1 is shutdown to see if things start flowing again? Can you give the details of Event 2080 in the Application event log on the Exchange server? Should see it once every 15 minutes.Tim Harrington | MVP: Exchange | MCITP: EMA 2007/2010, MCITP: Server 2008, MCTS: OCS | Blog: http://HowDoUC.blogspot.com | Twitter: @twharrington

Thanks Tim, I will try this later in the week and report back to you.

Hi, I would like to confirm the current situation. Does the email flow successfully after turning off the first DC more than 15 minutes? Regarding to the event error “Could not find any available Global Catalog in forest DOMAIN.local.”, I suggest you assure the DC2 is also a GC. If the issue persists, please restart the DC2 to check the result. For more information about the event error message, please refer to the following article: http://www.microsoft.com/technet/support/ee/transform.aspx?ProdName=Exchange&ProdVer=8.0&EvtID=4001&EvtSrc=MSExchange+System+Attendant+Mailbox&LCID=1033 Thanks. NovakPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

I had not had a chance to shutdown the servers in order to test. I will try to do it this weekend as it is something I need to do later in the evenings. Then I will update you.

OK. Please take some times to perform the suggestions. If there is any update, please let me know. Regards, NovakPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

I shutdown the main DC for an hour last night. No emails came in or out. In Event ID 2080 is as follows: Log Name: Application Source: MSExchange ADAccess Date: 1/8/2011 10:39:51 PM Event ID: 2080 Task Category: Topology Level: Information Keywords: Classic User: N/A Computer: Exchange.DOMAIN.local Description: Process MSEXCHANGEADTOPOLOGYSERVICE.EXE (PID=2080). Exchange Active Directory Provider has discovered the following servers with the following characteristics: (Server name | Roles | Enabled | Reachability | Synchronized | GC capable | PDC | SACL right | Critical Data | Netlogon | OS Version) In-site: XX.DOMAIN.local CD- 1 6 6 0 0 1 1 6 1 XXDC1.DOMAIN.local CDG 1 0 0 1 0 0 0 0 0 Exchange.DOMAIN.local CDG 1 0 0 1 0 0 0 0 0 Out-of-site:

Is it possible a Group Policy error could be a cause to this problem? I'm seeing errors when doing a "gpupdate".

On Sun, 9 Jan 2011 21:30:54 +0000, Ansky926 wrote: > > >I shutdown the main DC for an hour last night. No emails came in or out. In Event ID 2080 is as follows: > >Log Name: Application Source: MSExchange ADAccess Date: 1/8/2011 10:39:51 PM Event ID: 2080 Task Category: Topology Level: Information Keywords: Classic User: N/A Computer: Exchange.DOMAIN.local Description: Process MSEXCHANGEADTOPOLOGYSERVICE.EXE (PID=2080). Exchange Active Directory Provider has discovered the following servers with the following characteristics: (Server name | Roles | Enabled | Reachability | Synchronized | GC capable | PDC | SACL right | Critical Data | Netlogon | OS Version) In-site: XX.DOMAIN.local CD- 1 6 6 0 0 1 1 6 1 XXDC1.DOMAIN.local CDG 1 0 0 1 0 0 0 0 0 Exchange.DOMAIN.local CDG 1 0 0 1 0 0 0 0 0 Out-of-site: You have three DCs. Two of them (XXDC1.DOMAIN.local and Exchange.DOMAIN.local) are Global Catalog servers. None of your GCs are "reachable". Exchange.DOMAIN.local and XXDC1.DOMAIN.local: Roles: CDG Enabled: 1 Reachablilty: 0 <=== Synchronized: 0 GC Capable: 1 PDC: 0 SACL right: 0 Critical Data: 0 Netlogon: 0 OS Version: 0 The XX.DOMAIN.local machine isn't a GC. I'd say that you need to figure out why you can't contact the only GCs you have! Using DCDIAG and NETDIAG would be a good place to start. Moving your question/problem to one of the O/S forums to get help with the AD problem would be a good idea. Once you have the AD inftastructure sorted out if you still have Exchange problems then post the Exchange stuff here. --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

Thank you Rich for pointing me in the right direction. The domain controller that was not a GC was removed from the network as a DC. I only have two on the network. I will work on the issue as you've suggested.