Exchange

OCS follows Exchange into 64-bit-only land

Devin L. Ganger — Fri, 29 Aug 2008 20:07:05 GMT

You may have missed this interesting blog post this morning amidst all the political kerfuffle, so let me sum up: the next version of OCS will only support x64 platforms.

This isn't the big deal it would have been for OCS 2007. A lot of the initial FUD around the 64-bit-only move in Exchange 2007 turned out to be mere steam. While there were some initial challenges involved in managing the new 64-bit Exchange deployment from 32-bit machines, Microsoft got a lot of the licensing figured out and released the appropriate sets of tools to allow management of Exchange 2007 from both 32-bit and 64-bit environments. I fully expect that the OCS group has been paying close attention to all of this and taken good notes.

There's no denying that Exchange 2007 benefits from the "64-bit only in production" stance -- and with the release of Windows Server 2008 and Hyper-V, not to mention Microsoft's updated support statement for virtualization environments, the need for 32-bit environments is going away. My biggest reason for wanting 32-bit Exchange environments was so I could run demos under Virtual Server; now that I have Hyper-V, I'm probably not in any rush to go back to Virtual Server and the 32-bit limitation. 64-bit hardware is the norm today, and the x64 Windows variants are solid and mainstream enough for my dedicated application servers. (Maybe not so for the desktop quite yet, but still getting there rapidly.)

The one thing I'm skeptical about, though, is whether the move to 64-bits is really going to reduce the total number of servers in the deployment. In Exchange 2007, I only saw the server reductions in very large environments; the mailbox-per-server gains we got from 64-bits was offset by the explicit breakout of roles and the business needs that drove redundant configurations like CCR (which meant no co-locating roles with the Mailbox role) and multiple HT/CAS servers. I'm wondering how this is going to play out with the next version of OCS, where it already has so many distinct roles in play.

What I *hope* to see is that the maximum capacity of each server role (such as the number of users per pool or the number of streams per mediation server) can be driven upwards; this makes the large datacenter configuration options much more attractive, because it does translate to a reduced number of servers. However, for organizations that still have relatively low bandwidth separating their various locations, 64-bits won't do much to help; OCS deployment planning is very dependent on bandwidth, and is often the top limit on scalability long before the limits of the 32-bit Windows environment.

First Look at Microsoft Online Services: the Sign-In tool

Devin L. Ganger — Mon, 28 Jul 2008 18:30:18 GMT

Continuing from my previous post on MOS...

I didn't really mention this in the previous post, but MOS is designed to provide a hosted alternative to the server-side applications. One of the goals is to continue working with existing native clients and client access methods, so (for example) you can access your Exchange Online mailbox through OWA (running from MOS), through Outlook, or even through EAS/Windows Mobile. In order to do this, though, your client applications need to know how to talk to MOS and provide the proper credentials.

You can do this the hard way or the easy way. The hard way is running around and reconfiguring each application by hand and teaching your users how to use a separate set of credentials. The easy way is to use the MOS Sign-In tool, a little .NET 3.0 application that runs on the client desktop. It interacts with Outlook 2007 RTM/SP1, LiveMeeting 8, and IE7+.

When this application is run, it will invite the user to logon to MOS. The first time they do so, they're required to change their password. It then detects the apporpriate applications, offers to configure them to work with MOS, and then just sits quietly on the desktop, providing a seamless SSO experience.

To be continued...

First look at Microsoft Online Services: adding domains

Devin L. Ganger — Mon, 28 Jul 2008 18:21:46 GMT

I'm at an airlift here in Redmond for the new Microsoft Online Services (MOS), Microsoft's hosted services platform. Right now, MOS offers a combination of hosted Exchange (OWA, Outlook, and even EAS!), hosted SharePoint, and Live Meeting. We've just gone through an overview of the service, and it looks cool -- enough so that I'm now seriously considering switching my personal domains over to it (especially since they offer the ability to synchronize with your Active Directory deployment).

MOS is currently in beta and you can go sign up for a time-limited trial. There's only a certain number of trial accounts active at any given time, so your trial request may not be provisioned immediately; however, you can go to https://mocp.microsoftonline.com and sign up for one. You'll need a Windows Live account.

As you might imagine, MOS allows you to associate one or more DNS domains with your online account. When you register for your account, you're asked for a domain. This domain is not verified and, in fact, seems to be used simply as an internal administrative tag -- once your account and service is set up, you have to specifically add DNS domains. Adding them is a fairly simple process:

Register your domain name with a registrar.
Provision your domain with a DNS provider (often combined with step 1).
Add the domain name to your MOS Admin Center.
Run the verification wizard and add the auto-generated CNAME to your domain's DNS zone.
Validate the domain in the MOS Admin Center.
Start provisioning users with this domain, enable inbound e-mail on this domain, etc.

The verfication step is an important piece, because this helps MOS make sure that you're using a domain you're actually in control of. Otherwise, malicious people could sign in and hijack your domain, which would suck. The way Microsoft does this is actually simple and elegant: they generate a unique CNAME record (that looks very much like a GUID), and ask you to add this CNAME record, pointing back to a server under their control, to your zone. This has lots of advantages:

It's pragmatic. If you can add a CNAME record to a zone file, you effectively control the domain.
It avoids the nastiness that can result in WHOIS-based verification and allows people who register domains to continue using proxy companies, hiding their personal info from WHOIS spammers.
It's relatively easy. You simply have to add a simple record to your DNS; if you can't do this (or your DNS hoster can't do it for you), then you have much bigger problems managing your DNS and verifying your DNS domain under MOS is the least of your problems.
It's low-impact. The generated CNAME is highly unlikely to be queried during normal operations by your users; only MOS is likely to be looking for it. It doesn't require you to repoint your MX records or otherwise make major modifications to your infrastructure if all you want to do is start using online SharePoint and Live Meeting.

Note that just because you add a domain to MOS doesn't mean you have to use it for email! That's a separate operation, which is a two-step process of enabling inbound email for that domain and then updating your MX records appropriately.

More on other MOS functionality coming later...big thanks to the event staff for their kind permission for me to blog!

Hyper-V in the hizzouse!

Devin L. Ganger — Fri, 27 Jun 2008 03:28:20 GMT

Everyone's being so coy in the Windows blogosphere today. "As you may have heard..." Heck with that; this is wicked cool. Hyper-V has Released To Manufacturing ... and is already available for download. As the link explains, it'll start coming down the Windows Update pipe July 8th. If you don't want your Windows Server 2008 machine to be updated yet, don't be blindly accepting updates.

Why wouldn't you want to get it first thing?

You're running a previous version of Hyper-V. If so, be aware that upgrading your VMs is not automatic. It's not a horrible process, but it will take some time. You have to manually export each VM, remove the VMs from the server, upgrade the server, re-import the VMs, then update the Integration Services. The more VMs you have, the more time this will take.
You're running some software that is not yet compatible with Hyper-V RTM but works with an earlier build. In this case, you want to wait until that software has a patch available.

I fit into both categories. I think I'm going to wait until I'm back from vacation to do it.

Oh, yes, just because Hyper-V is now RTM doesn't mean that you can go run to install Exchange 2007 on it in production. See Scott Schnoll's post for more info.

These are not the solutions you're looking for

Devin L. Ganger — Fri, 27 Jun 2008 03:18:47 GMT

As IT professionals, we are more than often prone to fall to the perils of magical thinking. (I'm sure this is a side-effect of being human, which is a pesky and bothersome condition I will have to do something about one of these days.) Magical thinking in this context is when we have not internalized the intricacies of a problem and instead rely on formulas rather than true understanding to come up with solutions.

At one ISP I used to work at, we had a glorious reclaimed piece of technology, an Auspex NS-5500 file server. Every now and then on reboot, this old beast of a machine would fail to boot up; the cure was to open the cover over the drive cage and give it a good swift whack. We all assumed that this was because one of the drive connectors was a bit loose, but when our "magic" fix failed to work one night I discovered that it was in fact because one of the screws holding things in place was missing, allowing the drive bay to sag just a tiny bit. It was this tiny bit of sag that put just enough stress on the connector for drive 0. Had we actually opened the case up earlier, we'd have been able to solve the problem -- and prevent a year of whacking the server.

All too often, I see magical thinking in the field of security. Case in point: I recently heard about a gentleman who has a client that is requesting ETRN support be added back to Exchange 2007, either natively or through an add-on. They want to deploy the Edge role in their DMZ, have it queue up mail for the internal organization, and then have their Hub Transports (in the internal protected network) initiate a connection out to de-queue the messages using the ETRN SMTP extension. The reason they want this is that they've done due diligence and read some very thorough documents about computer network zones and have come to the conclusion that all network connections must be initiated from the most secure network. This, they say, removes the threat of malware taking over the Edge server in the DMZ and allowing an attacker to use it as a launching point to the protected network.

Now, the recommendation for connections to be initiated from a more secure network to a less secure network is a good general baseline to follow when it makes sense. However, it is not realistic in all cases (if we followed this to the letter, nobody would be able to receive e-mail from external senders except through random polling of Internet SMTP hosts, which is not at all scalable). This is doubly true if you don't understand how the underlying protocols work. Case in point: ETRN, defined by RFC 1985, "SMTP Service Extension for Remote Message Queue Starting". Quoting from section 3, "The Remote Queue Processing Declaration service extension" (emphasis added):

To save money, many small companies want to only maintain transient connections to their service providers. In addition, there are some situations where the client sites depend on their mail arriving quickly, so forcing the queues on the server belonging to their service provider may be more desirable than waiting for the retry timeout to occur.

Both of these situations could currently be fixed using the TURN command defined in [1], if it were not for a large security loophole in the TURN command. As it stands, the TURN command will reverse the direction of the SMTP connection and assume that the remote host is being honest about what its name is. The security loophole is that there is no documented stipulation for checking the authenticity of the remote host name, as given in the HELO or EHLO command. As such, most SMTP and ESMTP implementations do not implement the TURN command to avoid this security loophole.

This has been addressed in the design of the ETRN command. This extended turn command was written with the points in the first paragraph in mind, yet paying attention to the problems that currently exist with the TURN command. The security loophole is avoided by asking the server to start a new connection aimed at the specified client.

See the problem? ETRN was not designed to solve a security problem; it was designed to solve a financial problem back in days when always-on bandwidth was a lot more expensive and most ISPs metered traffic. It masquerades as solving a security problem only because it's designed to avoid a loophole in an insecure and exploitable feature. As a result, ETRN won't solve the problem these people want it to solve; all it does is tell the system in the DMZ to initiate a new connection to the Hub Transport servers. It doesn't reuse the existing connection initiated by the Hub Transport servers. They can't use a firewall rule to block outgoing access from the Edge to the Hub Transport and be safe, because they'll cut off all incoming traffic.

However, let us for a moment assume that it did work the way they wanted it to: my Hub Transport initiates an outbound SMTP session to the Edge. In this session, HT is the SMTP client, ET is the SMTP server. As soon as HT issues the ETRN command, they still have to swap roles -- HT is now using the SMTP server code paths, while the ET is using the SMTP client code paths. Any theoretical vulnerabilities that are in the HT SMTP implementation are still going to be there, still exposed to the message traffic about to be sent down the connection, still open to exploitation.

This is the magical thinking: firewalls and a DMZ will protect my traffic. This is not true; firewalls and networks zones are two components of a complete security plan. Neither firewalls nor network zones can protect legitimate traffic, nor are they designed to; they are designed to allow you to designate which traffic is legitimate. If you want to secure that traffic, you need to turn to other measures.

Tech-Talk: Making Backups Cool with DPM

Devin L. Ganger — Wed, 18 Jun 2008 17:55:50 GMT

While I was at the Tech-Ed NA IT Pro conference last week, Jason Buffington and I took the chance to invade the Tech-Ed Online fishbowl studio and record a quick Tech-Talk on using DPM. You can now view it online on the Tech-Ed IT Pro page and the Library page, or stream it directly. Now that Tech-Ed's over, maybe we'll both find the time to be on Xbox Live at the same time so we can continue our discussion in Call of Duty 4...

Updated Exchange Developer Roadmap

Devin L. Ganger — Tue, 17 Jun 2008 19:43:45 GMT

To reinforce yesterday's post about Exchange Web Services (EWS), I wanted to draw your attention to the Exchange Developer Roadmap posted on May 22 2008 on the Exchange API-spotting blog.

There shouldn't really be any surprises here, but there were a couple of items I wanted to highlight. First:

Given this commitment to Web services and our goal of making Exchange Web Services the richest developer interface for Exchange... (emphasis added)

Here's a preview of some of the functionality that we plan to add to the next release of Exchange Web Services:

Access to Folder Associated Items (FAI) and read/write access to user settings (Devin: this page in the MAPI reference indicates that FAIs are things like views and forms. I believe that this also fixes a known quirk of EWS that keeps you from creating Outlook-visible search folders that use certain property paths. I believe this also gives access to server-side rules, if they're not already accessible through a separate part of the API.)

Management of Personal Distribution Lists (Devin: very cool.)

Throttling capabilities that give Exchange administrators control over system resource consumption (Devin: this will be very nice for helping keep poorly written applications from taking down the Exchange servers.)

A powerful and easy-to-use server-to-server authentication model to enable building portals and enterprise mash-ups (Devin: let's hope this can ease some of the pain of building Exchange-aware SharePoint sites, at least those that don't require direct access to private mailbox content.)

An easy-to-use Microsoft .NET API that fully wraps the Web service calls, which makes Web service development even easier (Devin: I'll be interested in seeing how this stacks up against third-party offerings like the Independentsoft EWS client offering.)

Then they go on to list the APIs that will get removed (Exchange WebDAV, Store Events, CDO 3.0/CDOEx, and ExOLEDB) and moved to "extended support" (Exchange Server MAPI Client, CDO 1.2.1). Don't get too excited by the MAPI client -- it's not what you think:

Provides server applications a MAPI runtime for accessing Exchange.

Note: This is not the Outlook MAPI Client library that is included with Outlook.

and

Outlook's Exchange MAPI Store provider, available in the Outlook MAPI Client library can also be used to access an Exchange mailbox or public folder.

If you're going to start writing Exchange-aware applications, you should probably start looking at EWS first for future compatibility. If you're trying to support Exchange 2003 at the same time...good luck.

A .NET add-on for working with Exchange Web Services

Devin L. Ganger — Mon, 16 Jun 2008 18:10:20 GMT

I just got word that Independentsoft has come out with a beta version of an EWS client API for the .NET Framework and .NET Compact Framework. I've not looked at it yet, but I'm particularly hopeful about having a good way to work with EWS from Windows Mobile devices.

Exchange Web Services (EWS), introduced in Exchange 2007 and enhanced in Exchange 2007 SP1, is Microsoft preferred interface for all future programmatic reach into the Exchange store. While EWS is a Web service, it can be pretty complicated to work with. Luckily, we've done some work with EWS here at 3Sharp; Paul's been presenting some developer training sessions on EWS in partnership with Microsoft. We've found that Inside Microsoft Exchange Server 2007 Web Services has been a valuable reference on EWS.

One of the challenges for EWS development is that the schema and object model is pretty complex when compared with the typical Web service, enough so that you need to use special Visual Studio proxy classes when you use .NET to work with EWS. This, by the way, is very likely the cause of the compatibility issue I found between EWS and SharePoint Designer -- Designer's proxy classes aren't the EWS-aware ones.

Revised guidance on protecting Exchange with DPM 2007

Devin L. Ganger — Wed, 04 Jun 2008 19:36:11 GMT

Just a quick note to let you all know that the Protecting Exchange Server with DPM 2007 white paper is available for download from Microsoft. This is the same white paper I worked on for them last year, but freshly revised to include more guidance around mailbox-level recovery.

I'll be giving a talk around this topic next week at Tech-Ed (IT Pro) in Orlando, session number MGT369. Hope to see you there! (Yes, this is the same talk I did at Exchange Connections in Orlando and in MMS in Vegas a month ago; it seems to be a popular session!)

Three random links make a post

Devin L. Ganger — Mon, 02 Jun 2008 21:28:15 GMT

...so I'll throw in a fourth for good measure. Rather than try to write a full-length post about each of these, I'm just going to give you a quick bullet list:

Want to get the MAPI client or CDO libraries for Exchange 2007, or for Vista and Windows Server 2008? Wait no more: Microsoft Exchange Server MAPI Client and Collaboration Data Objects 1.2.1 is up on Microsoft Downloads.
Microsoft has done another cool thing: the Sysinternals tools are now available live from the Web. If you just need a specific tool, throw in the executable name to the URL and run it.
If you're trying to test a VSS writer, how do you do it? Start by downloading the VSS 7.2 SDK, which contains the vshadow.exe and BETest utilities. Optionally, you can also download the third-party utility Hobocopy.