[CentOS] Sendmail is considered deprecated

Sat Apr 1 01:03:14 UTC 2017
Peter <peter at pajamian.dhs.org>

On 01/04/17 09:57, Xinhuan Zheng wrote:
> Today I searched redhat official portal and learned that Sendmail is
> considered deprecated. By default, CentOS 7 will use postfix as MTA.

It is considered "deprecated" as you say, but that does not mean they no
longer support it.  You can use Sendmail in CentOS 7 just fine and it is
relatively easy to switch (complexities of proper Sendmail configuration
not withstanding).

I think in this case they simply mean that Sendmail is not the default,
but that does not mean it is not supported in any way.

> I need good advise on what it means to us. We are CentOS customers.
> We use that operating system for quite a few years. We rely on
> Sendmail for years for us to relay large quantity of emails to our
> customers for marketing purpose.

Admittedly this sounds like SPAM, but not all mass marketing mail is
SPAM and it can be done in a way which is not.  I'll give you the
benefit of the doubt for now.

> We build our additional fallback
> servers as well for fallback relays. We build our customized
> configuration for Sendmail too. I really need help to figure out if
> we can continue using Sendmail (even deprecated) for future long term
> and what implication would be doing so. Thanks,

I would say that Sendmail will likely continue to be supported at least
through the lifespan of RHEL7, I cannot speak as to whether it will be
supported in RHEL8 or not, but if you want to continue using Sendmail
and you feel comfortable using it, then by all means use it.

That said, I would encourage you to have a look at Postfix, you can do
pretty much everything you do in Sendmail in Postfix and more and the
configuration is easier to manage.  Postscreen is one of the newer
postfix features that you won't find in Sendmail and you may find that
alone is worth the switch.