Little problem with privatge ip's in e-mail detected by RBL's.

Richard G

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Jul 6, 2008
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Maastricht
Oke this is happening since a longer time, but did not have an issue with it before.

Lots of people (like me too) are sending mail via their email domain with an email client.
In my case I have domain company.nl and internet provider Ziggo.nl. I can't use port 25, which is limited to the smtp of Ziggo.

But I want email to be seen as coming from my domain.
So I send mail from [email protected] to [email protected] via the smtp server of my dedicated server where my domain resides so smtp.hostingserver.nl via port 587 to be able to send it.

Now with loads of internet providers, the dynamic ip ranges for their customers are listed in spamhaus, like Ziggo too.

This should be no problem as not the delivering system to [email protected] is in fact smtp.hostingserver.nl which also has a dedicated ip and rDNS, no issue there.

Nevertheless in some cases it seems to happen that RBL's or spamfilters are looking to the original helo name instead of from the delivering system.
So they also see the helo mypc1 which delivered the mail to my smtp server and so flags the mail as being listed on spamhaus. For example Mailwasher Pro does this too.

This can give issues as sometimes this legitimate email is seen as spam while it isn't.

Is this an issue we have to live with? Or can something be done to prevent this? As users should be able to send their mail via their domain on the hosting server without problems, correct?
 
I got a tip to add this in the exim.conf under:

remote_smtp:
add
headers_remove = Received:

I tend to test this, but I'm not sure how. Do I need to create a /etc/exim.custom.conf and just add this line? Or do I need to add it to exim.variables.custom.conf?
Can this be safely done or can this cause troubles?
 
Richard could also be if you received from Zigo (local) new IP and that Ip is "blacklisted"

( this was before always the maincause as customers of us not sending out mails, these ip's where on spamlists and so on.)

Lot of IP blocks and also on from ISP's are on spamhaus and so on.

Even problem with local mailserver here / client SMTP mailhost to DA server, the The spamhaus and rbl are still seeing your "dynamic" iSP IP mail sending from.
Here also this ip is in the SPF as Ok, but still some seeing as spam, don't know how outlook is doing right now.

Strange is not all Hotmail, Gmail gmx web.de and so on are going into spambox, so depends also on settings of the mailreceiving side

The dmarc reports are from all microsoft, yahoo, google PASS OK's here

If it is very important to be sure mail is delivered right we use roundcube, and not links in the mail and so on. ;)


IN test you could send from local mailclient and same adres from the roundcube webmail, to a test gmail,outlook account then read the differences in smtp headers there.
 
Last edited:
I don't have a mailserver at home but in the data center so that should not be any problem. Every Ziggo ip is blackilsted in Spamhaus by default, as is for many other providers too for being dynamic ip's.
I have the same ip for a long time and I normally don't have issues, it's once a while that this happens.

That's also the reason because it's so hard to test, I can send the same email 10 times for example from my outlook client, and maybe, just maybe once it gets rejected and the other don't have problems at all.

So hence my thought to remove the home email ip with this line in exim.conf but I don't know if it could cause other issues.
As I understood this is not quite according to RFC's, so if that's the case, I can better not do it because I would like all our mailservers to work according to RFC's to prevent problems with mail filters.
 
This has always annoyed me greatly. A while ago I was also searching for a way to remove my local IP (and even my 192.168xxxx!!) from the headers also for this reason. Why is this included by default?:confused: It's not something required to have for e-mail to function properly because the server (in this case Exim) sends it. It also isn't included if I send emails with Roundcube.

I don't think exim.variables.conf.custom is going to work because that isn't included in exim.variables.conf.
 
This has always annoyed me greatly. A while ago I was also searching for a way to remove my local IP (and even my 192.168xxxx!!) from the headers also for this reason. Why is this included by default?:confused: It's not something required to have for e-mail to function properly because the server (in this case Exim) sends it. It also isn't included if I send emails with Roundcube.

I don't think exim.variables.conf.custom is going to work because that isn't included in exim.variables.conf.

Yep me to, but hmm

Mailserver local is also sending over the DA exim HOST, still this IP's and therefore some possible spamblocking.

Just now send out (1 server DA and 1 localmailserver over smtp exim to a @live account , both received on the @live account of custommer. ( so so much depends on spamsettings and filters, as said google yahoo hotmail and so on the dmarc reports no problem, we have for main account a reject policy)

<adkim>r</adkim>

<aspf>r</aspf>

<p>quarantine</p>

<sp>reject</sp>

<pct>100</pct>

-<policy_evaluated>

<disposition>none</disposition>

<dkim>pass</dkim>

<spf>pass</spf>

</policy_evaluated>

</row>


-<identifiers>

<header_from>p.nl</header_from>

</identifiers>


-<auth_results>


-<dkim>

<domain>p.nl</domain>

<result>pass</result>

<selector>x</selector>

</dkim>


-<spf>

<domain>p.nl</domain>

<result>pass</result>

</spf>

</auth_results>

</record>

</feedback>
 
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