Updated 1401 PDT: added the diagram.
A recent post on a mailing list I frequent gives me today's blog post.
So you've got an Exchange 2000/2003 organization and you've decided that you want to upgrade to Exchange 2007. You've done all the research and planning and you've gotten as far as installing the first HT server (CF-EX01) into your organization:
- We'll assume that your organization already has an SMTP connector named Legacy SMTP to handle all outbound mail for the SMTP:* address space.
- Since this is the first Exchange 2007 server, Exchange 2007 Setup has created a new Exchange 2007-only administrative group and a new Exchange 2007-only routing group.
- It's also created a bi-direction Routing Group Connector between the HT server and the Exchange 2003 bridgehead (CF-LE01) you specified as your LegacyRoutingServer.
Let's take a look at things from EMS:
[PS] C:\>Get-RoutingGroupConnector | ft Identity,Cost,SourceTransportServers,TargetTransportServers
Identity Cost SourceTransportServ TargetTransportServ
Ers ers
-------- ---- ------------------- -------------------
CF-EX01-CF-LE01 1 {CF-EX01} {CF-LE01}
CF-LE01-CF-EX01 1 {CF-LE01} {CF-EX01}
[PS] C:\>Get-SendConnector
Identity AddressSpaces Enabled
-------- ------------- -------
Legacy SMTP {SMTP:*;1} True
As we expect, we see the pair of RGCs, each with a cost of 1, and our existing SMTP connector, also with a cost of 1. Right now, outbound message flow is easy: anything in the org only has one outbound gateway.
One of the first things you might want to do is get all inbound and outbound mail flowing through your new Exchange 2007 HT server. Inbound is easy: we simply change the configuration on our gateway mail machine or firewall server, or change our MX records, appropriately. For outbound, though, we want to create a new Exchange 2007 Send connector and test it before we actually entrust live email to it. Those of you with large Exchange organizations already know how to do this: manipulate your connector costs. If you're in a smaller organization that only had one routing group, though, this may be a new concept. Don't worry, it's pretty easy.
The goal is to create two outbound routes for the SMTP:* address space, one for the Exchange 2003 side of the organization and one for the Exchange 2007 side. The Legacy SMTP connector already gives us the former and we'll create the latter in a moment. We need to ensure that the costs of all related connectors are set so that:
- The combined cost of the Legacy SMTP connector, the RGC, and any other connectors in between is greater than the cost of the new Exchange 2007 Send connector from the Exchange 2007 routing group.
- Likewise, the combined cost of the new Exchange 2007 Send connector and the RGCis greater than the cost of the Legacy SMTP connector from the Exchange 2003 routing group(s).
To meet these goals, depending on how your organization is configured, you MAY need to mess with the default costs. In our sample organization where we have just two routing groups and we've used the default costs for all connectors, this is precisely how it all works out by default. First, though, let's go ahead and create the new Exchange 2007 Send connector:
[PS] C:\>New-SendConnector -Name 'New SMTP' -Usage 'Internet' -AddressSpaces 'SMTP:*;1' -IsScopedConnector $false -DNSRoutingEnabled $true -UseExternalDNSServerEnabled $false -SourceTransportServers 'CF-EX01'
Identity AddressSpaces Enabled
-------- ------------- -------
New SMTP {SMTP:*;1} True
[PS] C:\>Get-SendConnector
Identity AddressSpaces Enabled
-------- ------------- -------
Legacy SMTP {SMTP:*;1} True
New SMTP {SMTP:*;1} True
Yup -- two SMTP connectors, each with the SMTP:* address space and a cost of 1. Here's a quick diagram:
Now, let me show you how the routing currently works:
- From the Exchange 2007 routing group, we look for our lowest cost to the SMTP:* address space. We see two connectors that match.
- Our total cost to Legacy SMTP is 2, since its bridgehead is homed in the Exchange 2003 routing group. Cost 1 to navigate the RGC plus cost 1 for the connector.
- Our total cost to New SMTP is 1, since its bridgehead is homed in the same routing group we're in. This is our choice.
- From the Exchange 2003 routing group, we look for our lowest cost to the SMTP:* address space. Again, wee see the same two matching connectors.
- Our total cost to New SMTP is 2, since its bridgehead is homed in the Exchange 2007 routing group. Cost 1 to navigate the RGC plus cost 1 for the connector.
- Our total cost to Legacy SMTP is 1, since its bridgehead is homed in the same routing group we're in. This is our choice.
Now, we can begin our testing. We've got several ways to do this:
- Add an Exchange 2007 mailbox server, create a test account, create an Outlook profile, and go to town.
- Add a test mailbox to an existing Exchange 2003 mailbox server and set it up for IMAP/POP3 access. Use Outlook Express or Outlook to set up the mail account, and specify our Exchange 2007 Hub Transport server as the SMTP server.
- Telnet to port 25 of the Hub Transport server and submit messages manually. You might need to allow anonymous connections on the Default Receive connector if you do this, unless you can do NTLM and Base64 encoding in your head. (If you can, you scare me.)
Still with me? Whew! One last piece: we need to change the route costs when we're all done with our testing and are ready to flip the switch. Sure, you can do it from the GUI, but where's the fun in that? Simply use EMS to modify the address space on the Legacy SMTP connector to set its cost higher than the combined total of the RGC + New SMTP connector:
[PS] C:\>Set-SendConnector -Identity 'Legacy SMTP'-AddressSpaces 'SMTP:*;10'
[PS] C:\>Get-SendConnector
Identity AddressSpaces Enabled
-------- ------------- -------
Legacy SMTP {SMTP:*;10} True
New SMTP {SMTP:*;1} True
That, by the way, is how you update a cost: modify the AddressSpaces parameter on the connector. If you have multiple address spaces, this gets a little bit more complicated; you have to supply all the values instead of just one. We'll talk about techniques to do this later...perhaps in one of my upcoming sessions at Exchange Connections Fall 2007 in Las Vegas!