On 6/20/2011 9:52 AM, valdis.kletni...@vt.edu wrote:
On Mon, 20 Jun 2011 09:26:30 EDT, Steve Richardson said:
*definitely* concerns me. One thing they do say is that they need
several IPs per block to assign to their MTAs to handle such a large
amount of email (3 to 5 million per day). Being primarily focused on
layers 1 through 4, I don't have an incredible amount of experience
with high volume email server configuration, so I have no idea if they
are feeding me a line of BS or not.
It's BS. 5M a day is only about 60 per second, not at all a problem for a
single IP address running properly configured SMTP software.
For comparison, in the mid-90s, I was moving 1M RCPT TO's a day (and probably
half that number of envelopes) on a Listserv host using Sendmail on an IBM
RS6000-220 - a whole whopping 66MZ Power 604E processor and something like 64M
of RAM (The same basic firepower as an old Apple 6600 Mac, if you remember
them...) Doing 10M messages a day on a single box is *easy* these days - the
hardest part is getting a disk subsystem that survives all the fsync() beating
most MTAs like to dish out....
Well... 10M messages per day on a single box today would be fine for
hardware power, if most messages are accepted remotely on the first try,
but not necessarily doable in the SMTP environment of today. Mail
servers that send a lot of email have to hold a lot higher percentage of
messages in queue for longer today due to greylisting and other
deferrals - particularly from freemail sites.
Your customer should only need X addresses per block for SMTP load
sharing if they are going to have X number of physical servers. If they
are not going to have that many physical servers, then multiple
addresses in the same block per server provides no additional throughput
and could only be for block avoidance. SMTP servers do most of their
work managing mail queues - accepting new messages into queue, keeping
track of messages in flight (those that failed and need to be retried),
spoon feeding messages out to broken MTAs, etc... more IPs per box
doesn't help this.
Someone who expects to be "blocked occasionally" would only need two (or
a few...) address blocks. Someone who expects to be "blocked all the
time" would need *many* different discontiguous address blocks.
Are you getting spam complaints for their current blocks at an
unreasonable (to you) rate?
Are they doing all the right things with SPF, DK/DKIM (not an invitation
for a holy war on whether or not these are good or useful)?
If I put my tin foil hat on for a moment, I might suspect that your
email marketer may be feeling the pinch of the economic downturn and
might be considering implementing less scrupulous practices than they
have followed in the past. Even with my tin foil hat blocking out
external voices... most internal voices agree that this sounds spammy.
-DMM
