[CentOS] DKIM

mouss mouss at netoyen.net
Thu Sep 25 14:20:09 UTC 2008


Kai Schaetzl wrote:
> Ralph Angenendt wrote on Wed, 24 Sep 2008 20:23:50 +0200:
> 
>> That's supposed to help with what regarding his problem?
> 
> Hotmail seems to delete all mail from domains without SPF if it's not 
> coming from the MX. Yahoo might be doing the same.
> 

oh please no. hotmail don't delete my mail and I don't have an SPF 
record. no do yahoo/gmail. and this was before I implemented DKIM. and 
I've recently worked for a project where SPF didn't help with hotmail 
(delivery from an old server was ok, so we had to keep relaying to 
hotmail via the old server).

all the gorillas have complex filtering methods. An important part of 
this is the reputation of the sending IP. In particular:

- if you inherit an IP with a bad reputation, don't be surprised to 
start with a bad reputation.

- if you get a new IP for your domain, be ready to get "ignored". the 
default for a new IP is "this is probably not a mail server". you'll 
have to do some work to move to "this may be a mail server".

- if your IP is in a range and your IP is unknown, then you inherit the 
range reputation. This should be clear, whether you think it's good or not.

- if your range is unknown (no reputation data), the reputation is 
computed automatically. A range where a lot of IPs are "unknown" will 
get a bad reputation. A range where a lot of IPs "look dynamic" will get 
a bad reputation.

the common "I am innocent until proven guilty" doesn't apply here. sure, 
you're innocent and I am not going to put you in jail. but I am not 
going to let you in if "I don't feel it".


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