Re: Comcast & Greylisting

Brian Ross wrote:
> I recently noticed that Comcast and greylisting don't seem to get 
> along....  They appear to be originating mail from the following IPs:
>
> 	+-----------------+
> 	| relay_ip        |
> 	+-----------------+
> 	| 204.127.192.83  |
> 	| 204.127.192.84  |
> 	| 204.127.200.81  |
> 	| 204.127.200.85  |
> 	| 204.127.225.91  |
> 	| 204.127.225.93  |
> 	| 204.127.225.94  |
> 	| 206.18.177.53   |
> 	| 206.18.177.54   |
> 	| 216.148.227.153 |
> 	| 216.148.227.154 |
> 	+-----------------+
>
> Which resolve to the following names:
> 	alnrmhc11.comcast.net
> 	alnrmhc13.comcast.net
> 	alnrmhc14.comcast.net
> 	rwcrmhc13.comcast.net
> 	rwcrmhc14.comcast.net
> 	sccrmhc11.comcast.net
> 	sccrmhc15.comcast.net
>
> Which is interesting because when you look closer there appear to be 
> multiple IPs bound to each of their outbound servers and those IPs 
> are on completely different subnets (which is where greylisting is 
> getting broken, I assume):
>
> 	alnrmhc11.comcast.net   A       204.127.225.91
> 	alnrmhc11.comcast.net   A       206.18.177.51
>
> Does anybody have some secret sauce to deal with this?  I'm loathe to 
> just blanket whitelist these IPs.....
>   

You don't need to whitelist them completely, just bypass greylisting -- 
greylisting is useless against legitimate servers, if you KNOW a server 
is going to retry you may as well not bother greylisting it and save 
both of you a little bandwidth.

-- 
This signature does not exist.