Posts Tagged ‘Exchange’

The 3 Copies Benefits for Hosting companies #Exchange #Exchange2010 #Microsoft

October 25, 2011 Leave a comment

Last week, I went through a very interesting discussion with one of my customers who is implementing one of the largest Exchange cloud in the region, they are currently in the planning phase.

the discussion occurred during our design session planning for the overall implementation, the discussion started with the question of Storage design and RAID level required.

the storage that were calculated to host the projected hosted mailboxes were about 26 TB of data for 2 copies (around 13 TB) per copy.

the question that we got, now we will need to design our RAID storage, how many disk is needed? we will need a lot of disks!!!!

I paused a little and said, Why you will need to do RAID, there is actually a better way that will save you money and even  offer better and more services to you customer, I paused “as part of the excitement process Smile“ and said “Use 3 copies of Exchange 2010”.


my customer has a reputable SAN from a very reputable vendor, they have shelves and money to buy the shelves, but yet each penny you add to the solution will affect the final offering to the customers which is correct and true.

let us take for example, suppose that you want to host 10,000 users with 512 MB quote, and suppose that your Exchange factors will maintain the same factors you will do for Enterprise use (Like Deleted Items retention, overheads…etc). if you used the Exchange calculator this will lead you to need around 10 TB per copy (DB + Logs) and 20 TB per environment, and total required 1200 IOPs. ( to reach the same calculation, use the Exchange Storage Calculator).

of course I am not talking about the penetration factor and over-subscription factors that you as ISP might use during the calculation, you might assume that you have 10% of concurrency and usage or you might go with 90% this will be totally based on your marketing and strategy teams decision.

so to host the 10,000 users , 10 TB of data on RAID 5 or even RAID 10, let us see how many disk is needed.

using you will be able to set the storage and required IOPs, assuming 15 K, 450 GB disks, you will find that to accommodate all of the databases on single big RAID 5 LUN you will need it to be generated from 36 Disks which provides the required storage and around 2471 IOPs (obviously there is a lot of waste in the IOPs)

same calculation can be done with SATA Disks and that will leave you with about 21 * 1 TB disks which leaves you with 619 IOPs (limited set of IOPs) with about 13 TB of storage.

now let us go back to my suggestion, my suggestion was not to use any RAID level protection, using SATA disks and 3 Exchange nodes hosting the Exchange 2010 Databases, let us investigate the options:

  Using 15 K, 450 GB Disks Using 1 TB SATA Disks Using 3 Nodes Copy (single Disk 2 TB per DB)
Usable Storage 10058 GiB 14901 GiB 1 TB
IOPs 2574 644 70
No. of Disks Per Copy 36 21 14
Total Disks for environment 72 42 42
User Quote 512 MB 512 MB 512 MB
Possible Increase in quote None 250 MB 250 MB
No. of Users per 1 TB storage (max recommended DB size) 1562 1200 1400
Max. No of supported users 10,000 10,000 14,000 (this is based on the calculation that assumes 512 MB with 1.25 overheads)


The Possible Increase in quote calculated by available space that still remains on the disk divided by no. of users hosted per LUN which is 1 TB size.

for SAS/FC disks the maximum users per DB is based on the recommendations of max of 1 TB DB size, size overheads are set to 1.25, so space and max. users is limited with available usable space.

for SATA disks, the max of users determined and limited by max of IOPs that could be generated from the RAID Group.

it is much clearer for you know that with the use of 3 copies, you might have the same amount no. of disks used with 1 TB RAID 5, but you will enjoy larger mailboxes that you can offer for your customers without adding any cost to your investment or have more users capacity without sacrificing performance, adding the capacity to remove backup need and much simplified storage management (with the option of SAN elimination).

You Cannot open OWA Interface after applying Exchange 2010 SP1 #Microsoft #Exchange2010

October 2, 2011 1 comment

Consider the following scenario:

you have Exchange 2010 RTM infrastructure up and running, you applied SP1 to the servers, after applying Exchange 2010 SP1 you lost access to the OWA Virtual Directory, when accessing the OWA virtual directory you might get:


Internet Explorer cannot display this page


Could not load file or assembly ‘Microsoft.Exchange.Diagnostics, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35’ or one of its dependencies. The system cannot find the file specified.


when opening the OWA virtual director application path you get “invalid application path”


there are several root causes of this issues, below are my findings for the cause of these errors:


you are using wrong redirection configuration to redirect http to https traffic, the correct way to configure Exchange 2010 to redirect http to https traffic could be found here

using other techniques will lead to OWA loading errors.


Wrong configuration in the OWA web.config application, to correctly load it rename the file to web.config.old and restart iis.


in-complete SP1 or RU installation, try to remove SP1/RU and install it again.


I found the above issue on servers that had IE9 installed, didn’t have the chance to test whether uninstalling IE9 fixed the issue or not, as un-installing IE9 was taken among other steps to fix the issue, but if you might want to take a look to IE9.

Book review: Microsoft Exchange 2010 PowerShell Cookbook #Microsoft #Exchange #Exchange2010

August 18, 2011 1 comment

ms powershell

Have been reading Microsoft Exchange 2010 PowerShell Cookbook for the last few days and couldn’t stop until I finished it, summary it is amazing book.

The book is written into cookbook style so it doesn’t waste your time in useless introductions and chapters it goes directly into PowerShell introduction chapter and after that goes into delving into most of the commands system admin/consultant/implementer might need.

Have to admit that by reaching page 20 I started to read new information and hints, I loved the problem introduction and how do I style so the book says Mark want to import mailboxes to users from CSV, and then follows it with how do I and adds extra section to extend it maybe using variables..etc

Mike Pfeiffer have done a great effort with the book, and covered almost everything from installation to advanced administration covering most of the common and advanced tasks and introducing new hints and scripts like in the chapter of monitoring server health and managing mailboxes it is full of handy scripts that will help you in managing, reporting and logging mailboxes and servers.

you have to get that book into your library, you can buy it from here and you won’t regret it.

#Kemp hardware load balancer sizing guide

June 14, 2011 Leave a comment

I just spotted a very cool sizing calculator for Kemp Hardware load balancer, this is a very awesome tool for Exchange and Windows administrators who are looking for sizing guides for their HLB ordered from Kemp. you can access it from here.

an awesome tool and must see.

New #Exchange 2010 Custom KBS #Exchange2010 #KBs

April 11, 2011 1 comment


A user who is trying to access his archived mailbox in OWA might receive:

The item you tried to access no longer exists.
The item wasn’t found.  You or a delegate might have moved or deleted it using another computer or a mobile phone


here is a known issue:

Error occurs when trying to open a message attached .ics file in Archive mailbox.
The entire error message is as following.
The item you tried to access no longer exists.
The item wasn’t found. You or a delegate might have moved or deleted it using another computer or a mobile phone.
This issue occurs when the view is change to the Conversation view.
This issue occurs when a message attached .ics file is in a folder under Archive mailbox.

This will be Fixed in later Updates


you might Receive errors when configuring IRM service point and test-irmconfiguration cmdlet:

C:\Program Files\Microsoft\Exchange Server\V14\Scripts>Set-IRMConfiguration -InternalLicensingEnabled $true
No connection could be made because the target machine actively refused it —> Unable to connect to t
he remote server —> Failed to get Server Info from
    + CategoryInfo          : InvalidOperation: (:) [Set-IRMConfiguration], Exception
    + FullyQualifiedErrorId : 8E3210B2,Microsoft.Exchange.Management.RightsManagement.SetIRMConfiguration

[PS] C:\Program Files\Microsoft\Exchange Server\V14\Scripts>Test-IRMConfiguration

cmdlet Test-IRMConfiguration at command pipeline position 1
Supply values for the following parameters:
Sender: ************

Results : Checking Exchange Server …
              – Exchange Server is running in Enterprise.
          Loading IRM configuration …
              – IRM configuration loaded successfully.
          Retrieving RMS Certification Uri …
              – RMS Certification Uri:
          Verifying RMS version for
              – Warning! Failed to verify RMS Version. IRM features require AD RMS on Windows Server 2008 SP2 with the
          Hotfixes specified in Knowledge Base article 973247 ( or RMS on Window
          s Server 2008 R2.
          Microsoft.Exchange.Security.RightsManagement.RightsManagementException: Failed to get Server Info from https:
          // —> System.Net.WebException: Unable to connect to the rem
          ote server —> System.Net.Sockets.SocketException: No connection could be made because the target machine ac
          tively refused it
             at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
             at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket& soc
          ket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Int32 timeout, Exception& except
             — End of inner exception stack trace —
             at System.Net.HttpWebRequest.GetRequestStream(TransportContext& context)
             at System.Net.HttpWebRequest.GetRequestStream()
             at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters)
             at Microsoft.Exchange.Security.RightsManagement.SOAP.Server.ServerWS.GetServerInfo(ServerInfoRequest[] req
             at Microsoft.Exchange.Security.RightsManagement.ServerWSManager.ValidateServiceVersion(String featureXPath
             — End of inner exception stack trace —
             at Microsoft.Exchange.Security.RightsManagement.ServerWSManager.ValidateServiceVersion(String featureXPath
             at Microsoft.Exchange.Management.RightsManagement.IRMConfigurationValidator.ValidateRmsVersion(Uri uri, Se
          rviceType serviceType)
             at Microsoft.Exchange.Management.RightsManagement.IRMConfigurationValidator.TryGetRacAndClc()


Make sure that the following hotfix is installed:


Disable Anonymous access on servicelocator.asmx page


Users running Outlook 2003 might not be able to see full Free/Busy Information:


This is because in SP1 outlook 2003 publishes free/busy information but only can view 60 days of information (1 month after and 1 month before), there is no workarounds per my knowledge.


when you move a user from Exchange 2003 to Exchange 2010 you might get the following error:

[PS] C:\>New-MoveRequest –Identity ‘’ -TargetDatabase ‘Mailbox Database 0036434759’
Mailbox database ‘ad2f88b9-670e-4cfb-a91c-5f9f10f3da04’ is offline.
    + CategoryInfo          : NotSpecified: (0:Int32) [New-MoveRequest], RemoteTransientException
    + FullyQualifiedErrorId : E9F32A3C,Microsoft.Exchange.Management.RecipientTasks.NewMoveRequest


Make sure that inheritable permissions are propagating on the user’s mailbox.

Is it ok to remove Exchange Server objects using ADSIEDIT #Exchange #Exchange2010

February 17, 2011 2 comments

usually when people facing a failed exchange server or failed installation, admins/consultants were using the ADSIEDIT tool to remove the Exchange server object from active directory, people were using this article

I have seen an internal discussion that shocked me, for years I was using this article to remove failed Exchange2010/2007 Servers from AD, I know that I can use the recover option but it was fast and easy to use ADSIEDIT and as long it is ok to use it.

The discussion was about how safe it is using ADSIEDIT to remove Exchange server object from AD, surprisingly the response was that it is not recommended for Exchange 2007/2010 to use that method, also the above KB only applies for Exchange 2003, and there is no documented way to manually remove Exchange 2007/2010 and the only way to do it is using the setup /m:recoverserver, Thus using ADSIEDIT is not recommended nor supported.

Microsoft recommends only using ADSIEDIT only as a last resort if nothing works.

I know that it was popular even on the forums to use ADSIEDIT, from now and on use it only if server recovery failed.

more references:

Recover an Exchange Server

#Exchange #Exchange2010 a deeper look to the UM Worker Process and WP Recycling

December 30, 2010 2 comments

A Deeper look to UM Process, Worker Process and Recycling:

Couple of days ago a thread came across in front of me,  that talks about the UM worker process and UM Service and I wanted to share the info with you.

As all of us know, the UM server is the server that provides Voice Mail, Outlook Voice Access and other Exchange cool voice features to users in the Exchange organization.


There 2 very important processes within the UM server

The MS Exchange UM Service and the Exchange Unified WP (check the above diagram).

The MS Exchange UM service  is lightweight service that accepts connection on port 5060 or 5061 (depends on the security level of your SIP connection) but doesn’t handle the media stream but itself, this is handled by the EUWP.

How, the UM service accepts the connection from the SIP endpoint (whatever it is) and send to it SIP 302 redirect message to the port 5065 and 5066 (where the actual media is passing).

The Worker Process service is the service that handles the actual media, it doesn’t listen on 5061 it listens on either 5065 and 5066.

The idea that the WP RECYCLE itself every 7 days (this is to reset the WP because of the heavy loads due to voice mails..etc) so it needs to reset itself.

This causes the WP to recycle every 7 days and listen for a week on port 5065, and then listen for another week on 5066 and going back and forth like that.

This has been around since Exchange 2007 RTM, but since Exchange 2010 SP1 there is has been some reports that some PBX (like Nortel CS 1000, and Cisco CCM 6) not working with the Exchange 2010 SP1 UM, this could be due how Exchange 2010 SP1 constructs the 302 redirect message but no solid clues on that one, thus some users running on those PBX might not some drops in the voice mail call during the WP recycle.

NOTE: editing the Recycle schedule is not supported by Microsoft


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