Splitting the SMTP Environment
Fortunately, we have multiple
options for this task. The following are the options we have tested and
used in production environments:
- Use an Internet domain
for Notes and another for Exchange. Perhaps your company is
comprised of individual companies. In other words, the Notes
environment collects Internet mail for company1.com and the Exchange
environment collects mail for company2.com. This is the safest and
easiest to configure.
- Establish sub domains
(an internal partitioning scheme) to identify each mail system.
For example, notes.company.com could be used internally to identify
the Notes users and exchange.company.com could be used (also
internally) to identify the users on the Exchange system. The delicate
areas are (1) internal naming structure and (2) how inbound mail will
be processed. Many companies who use this strategy have a virus
scanner or other SMTP server that scans and relays inbound mail.
A
mapping table on this server would receive mail for
steve@company.com, lookup the internal address of
steve@exchange.company.com, and route the mail to the Exchange
servers for processing. Also, these servers can be used to modify
outbound mail, so if
steve@exchange.company.com sends mail, the SMTP relay server would
strip exchange from the address so that folks in the real world would
see
steve@company.com as the reply address. One drawback is that these
mapping tables often require manual updates. The primary benefit is the
ease at which multiple internal servers can share the domain name. We
have worked with customers who have Exchange, Notes, GroupWise and
various SMTP servers sharing the same domain by creating an internal
partitioning scheme such as the one just mentioned.
 Split
the domain. Splitting the domain is tricky, but it provides a
seamless border between multiple systems. In essence, the Exchange
server will forward unresolved mail to the Notes system and
visa-versa. There are several TechNet articles that describe this
process from the Exchange perspective and similar documents on IBM’s
web site for configuring this process to work with Notes. The routing
process works as follows:
- Either system receives an
inbound message that is not resolved to a local mailbox or person
document.
- The server then forwards
the unresolved message to the IP address (of the other mail system)
you specify in the Configuration document or SMTP settings.
- The message is either
delivered or a Non Delivery Report (NDR) is created.
The
drawback to this option is that NDRs will be created by the alternate
system, and this configuration is slightly more difficult to setup and
support. This option also does not support as many internal systems
types as option 2. The benefit is that everyone in the company can share
the same company.com address for internal and external messages. |
