Whitelisting RBL domains
I have one customer receiving emails from one cloud service which uses different ips:
and some times that cloud service falls in some RBL spam lists:
I was not able to find a way to bypass the RBL checking for any "cloudfilter.net" subdomain. Documentation in CPanel about the option /etc/skiprbldomains is not very complete: "wildlsearch or nwildlsearch: These search a file linearly, like lsearch, but instead of being interpreted as a literal string, each key in the file may be wildcarded.[...] The following forms of wildcard are recognized: *.a.b.c data for anything.a.b.c *fish data for anythingfish"
Why the Exim wildsearch key doesn't work?
omta37.uswest2.a.cloudfilter.net 35.89.44.36
omta037.useast.a.cloudfilter.net 44.202.169.36
..etcetera. and some times that cloud service falls in some RBL spam lists:
# exim_checkaccess 44.202.169.36 customer@address.com
Rejected:
550-"JunkMail rejected - omta037.useast.a.cloudfilter.net [44.202.169.36] is in
550-an RBL: IP 44.202.169.36 ......I was not able to find a way to bypass the RBL checking for any "cloudfilter.net" subdomain. Documentation in CPanel about the option /etc/skiprbldomains is not very complete: "wildlsearch or nwildlsearch: These search a file linearly, like lsearch, but instead of being interpreted as a literal string, each key in the file may be wildcarded.[...] The following forms of wildcard are recognized: *.a.b.c data for anything.a.b.c *fish data for anythingfish"
Why the Exim wildsearch key doesn't work?
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finally I have included a partial-lsearch in this line of the Exim advanced editor "hostlist greylist_common_mail_providers = partial-lsearch;/etc/greylist_common_mail_providers" because the line "!hosts = +greylist_common_mail_providers" exists in every RBL list Then I have included *.subdomains inside empty file /etc/greylist_common_mail_providers, and chattr +i the file to avoid changes. Hope it can works. Anyway, some option to whitelist domain hostnames is very needed. There are services of that style who are renting many Amazon AWS and similar solutions to use many host subdomains with different ips to send legitimate e-mail. A perfect option to avoid breaking the anti-spam filters in all the server would be whitelisting *.domains for concrete email addresses. 0 -
Thanks for sharing that solution!!! 0
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