[mailop] IPv6 reverse DNS from office365
Hi, Is anybody else having trouble relaying email out of office365. I think they have broken their reverse DNS. Our method to trust *.outbound.protection.outlook.com 2022-02-10 09:51:46 H=(GBR01-LO2-obe.outbound.protection.outlook.com) [2a01:111:f400:7e15::200] When we receive from 2a01:111:f400:7e15::200 this reverse lookups to mail-lo2gbr01lp20200.outbound.protection.outlook.com. but when you forward check mail-lo2gbr01lp20200.outbound.protection.outlook.com. it resolves to ::1 Which is when I think exim goes `I'll ignore than DNS record` I'm just interested if anybody has the same problem. A new problem that started sometime since 2022-02-09 20:39:38 UTC. (our users don't send much email over night in UK time. Tim Bray ___ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
Re: [mailop] IPv6 reverse DNS from office365
On Thu, 10 Feb 2022, Tim Bray via mailop wrote: Hi, Is anybody else having trouble relaying email out of office365. I think they have broken their reverse DNS. Our method to trust *.outbound.protection.outlook.com 2022-02-10 09:51:46 H=(GBR01-LO2-obe.outbound.protection.outlook.com) [2a01:111:f400:7e15::200] When we receive from 2a01:111:f400:7e15::200 this reverse lookups to mail-lo2gbr01lp20200.outbound.protection.outlook.com. but when you forward check mail-lo2gbr01lp20200.outbound.protection.outlook.com. it resolves to ::1 Which is when I think exim goes `I'll ignore than DNS record` I'm just interested if anybody has the same problem. A new problem that started sometime since 2022-02-09 20:39:38 UTC. (our users don't send much email over night in UK time. I can confirm that there's something weird with their DNS with IPv6. $ dig +short GBR01-LO2-obe.outbound.protection.outlook.com 2a01:111:f400:7e15::200 $ dig +short -x 2a01:111:f400:7e15::200 mail-lo2gbr01lp20200.outbound.protection.outlook.com. $dig +short mail-lo2gbr01lp20200.outbound.protection.outlook.com ::1 Using A (IPv4) records there's no issue. Cheers.___ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
Re: [mailop] Google considers DMARC reports to be unsolicited mail :(
This type of question comes up other times, and really this applies to the same case. Which is to say, yes, we run spam filtering on these types of addresses, same as we do for postmaster@ or abuse@. These addresses are heavily spammed, disabling the spam filter isn't a good idea. That said, it is true that dmarc reports at least should be in a certain format according to the spec, so we can do a better job with properly formatted messages. I've filed a bug for that. Brandon On Tue, Feb 8, 2022 at 11:11 PM Bernardo Reino via mailop wrote: > Dear all, > > I have already experienced Google ratelimiting DMARC reports every now and > then, > which may be OK if they want it like that.. but this is new (to me): > > Reporting-MTA: dns; katara.bbmk.org > X-Postfix-Queue-ID: 3D2D71BE02E2 > X-Postfix-Sender: rfc822; rep...@dmarc.bbmk.org > Arrival-Date: Wed, 9 Feb 2022 07:01:03 +0100 (CET) > > Final-Recipient: rfc822; mailauth-repo...@google.com > Original-Recipient: rfc822;mailauth-repo...@google.com > Action: failed > Status: 5.7.1 > Remote-MTA: dns; aspmx.l.google.com > Diagnostic-Code: smtp; 550-5.7.1 [65.108.69.105 12] Our system has > detected that this message is 550-5.7.1 likely unsolicited mail. To > reduce > the amount of spam sent to Gmail, 550-5.7.1 this message has been > blocked. > Please visit 550-5.7.1 > https://support.google.com/mail/?p=UnsolicitedMessageError 550 > 5.7.1 for > more information. e21si14404251ljg.437 - gsmtp > > I guess there's nothing to do, but I find this irritating.. I mean, they > could > just stop requesting DMARC reports instead of requesting and refusing > them? :) > > Cheers. > ___ > mailop mailing list > mailop@mailop.org > https://list.mailop.org/listinfo/mailop > ___ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
Re: [mailop] IPv6 reverse DNS from office365
On 2022-02-10 at 05:16:47 UTC-0500 (Thu, 10 Feb 2022 10:16:47 +) Tim Bray via mailop is rumored to have said: > When we receive from 2a01:111:f400:7e15::200 this reverse lookups to > mail-lo2gbr01lp20200.outbound.protection.outlook.com. > > but when you forward check > mail-lo2gbr01lp20200.outbound.protection.outlook.com. it resolves to ::1 Yes, Microsoft has a chronic endemic problem of broken reverse DNS, in both IPv4 and IPv6. It cannot be relied upon. MOST of their active sources are fine: HELO and PTR agree and their names resolve back to their client IPs. Some are just wrong for no obvious reason and with no obvious pattern. -- Bill Cole b...@scconsult.com or billc...@apache.org (AKA @grumpybozo and many *@billmail.scconsult.com addresses) Not Currently Available For Hire ___ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
Re: [mailop] IPv6 reverse DNS from office365
On Thu, Feb 10, 2022, Bill Cole via mailop wrote: > Yes, Microsoft has a chronic endemic problem of broken reverse DNS, > in both IPv4 and IPv6. It cannot be relied upon. So does Google reject mail from those misconfigured Microsoft systems? -- Please don't Cc: me, use only the list for replies. ___ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
[mailop] Anyone from Centurylink.net (or related) on list?
Hey there, We've been receiving some rejected messages from Centurylink.net along with a few other domains with the exact same rejection message which seems to suggest they are all related: centurylink.net tds.net cableone.net wowway.com embarqmail.com I couldn't find any postmaster addresses publicly available, but reached out to some abuse addresses I was able to find, but haven't had any response. Any help would be much appreciated. Omid Majdi Product Lead DuckDuckGo, Inc. ___ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
Re: [mailop] Anyone from Centurylink.net (or related) on list?
Omid: try t...@synacor.com. Udeme On Thu, Feb 10, 2022 at 5:59 PM Omid Majdi via mailop wrote: > Hey there, > > We've been receiving some rejected messages from Centurylink.net along > with a few other domains with the exact same rejection message which seems > to suggest they are all related: > > centurylink.net > tds.net > cableone.net > wowway.com > embarqmail.com > > I couldn't find any postmaster addresses publicly available, but reached > out to some abuse addresses I was able to find, but haven't had any > response. Any help would be much appreciated. > > Omid Majdi > Product Lead > DuckDuckGo, Inc. > ___ > mailop mailing list > mailop@mailop.org > https://list.mailop.org/listinfo/mailop > ___ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop