[CentOS] another SMTP auth question

Thu Mar 9 00:15:58 UTC 2017
Fred Smith <fredex at fcshome.stoneham.ma.us>

My ISP has just informed me that we will soon be required to authenticate
when connecting to their smtp server, so I've been looking around on the
web for how to do that with sendmail (just using auth when connecting
outward-bound, nothing else).

I've found a page here: http://www.sendmail.org/~ca/email/auth.html
that explains it simply (for simple minds, like mine) but it appears
to be old-ish.

So, I'm wondering if the recommendation of using:


is still appropriate, since MD5 is known to be breakable. Are there other hash
mechanisms that can be used in SMTP for this purpose?

Also, if someone can help me understand the syntax, I'd appreciate it:
does EXTERNAL mean some external tool not specified here? if so, how
is it specified? what such tools would be appropriate?

is there something more robust, e.g., sha256 or similar that should
be used here instead?

is GSSAPI internal, or does the external mean EXTERNAL GSSAPI?

Thanks in advance for any tips.

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