Exchange routing considerations

- Internal messages always go for shortest route available
- A connector will be considered off ONLY when all bridgehead server(s) on that connector are down
- For external messages, a route is chosen with closest SMTP name space matching first regardless the cost. For example, an email destined to *.net will go to connector that is responsible for *.net even it has higher cost than the one that is responsible for * space.
- Routing does not fail over from a connector with a specific address space to a connector with a less specific space. So when there is problem with all *.net connector(s), emails will be queued up in *.net connector(s)
- The above 2 rules don’t apply to user who doesn’t have permission to the specific connector. Consider connector that a user doesn’t have permission as non-exist when routing his emails.

SMTP Virtual Server vs. SMTP Connector

SMTP Virtual Server vs. SMTP Connector
1. SMTP virtual server is the protocol stack that actually does the work - sending/receiving SMTP emails. SMTP virtual server alone gives you ability to send/receive Internet emails.
2. SMTP Connector is built on the top of virtual server and provides you more control - such as dispatching emails to different domains to different routes, applying different restrictions, etc.
3. SMTP virtual server only sends/receives emails to/from the IP address it is bound.
4. As for DNS, either specify external DNS servers on SMTP virtual servers or specify forwarder on DNS server that Exchange server uses.
5. The benefits of SMTP Connector are 1) ease of administration; 2) to simplify troubleshooting when issue surfaces.
6. You can either have your SMTP connector delivery the emails directly (given that the connector is able to resolve external domain names - using one of 2 settings in item 4 )
- or -
You can have your SMTP connector forward all emails to a smart host. Although you can specify a smart host on an virtual server, it’s better to set it on the connector. The smart host setting on the connector overrides any smart hosts on the virtual server.

VBscripting tips

1. To make sure you fetch the output only after the command finishes, add the following between shell.exec and stdout.all
   Do While oExec.Status = 0
   WScript.Sleep 100
   Loop
2. To pipe output from one process to another
   Dim oUserDN

• set oShell = createobject("wscript.shell")
  mystr = "dsquery user -samid %username% -o dn dsget user -memberof"
  set oUserDN = oShell.exec("%ComSpec% /c """ & mystr & """")
  Wscript.Echo oUserDN.StdOut.readall