Home

Host not found mail.protection.outlook.com

Highlighted
Miroslav Gago
Occasional Visitor

Hi,

we use MS EXCH 2k10 with Postfix frontend and there is a major issue with DNS resolution of mail.protection.outlook.com domains on Postfix servers. These servers are using BIND 9.9.5 nameservers. Sometimes (and this is interesting, it does happen just sometimes) there are outgoing mails in Postfix queue with this status:

 

(Host or domain name not found. Name service error for name=XXXX.mail.protection.outlook.com type=A: Host not found, try again)

 

Just mail.protection.outlook.com domains does this. Digging this domain ends up with SERVFAIL but after some time it returns NOERROR with correct IPs from this domain. Then I have to manually flush Postfix queue to send this messages asap.

 

Can you give some advice why this is happening?

2 Replies
Highlighted

Not an advisor, but our client with an account at outlook.com have the same everyday repetitive problem.  Some outbound messages during the HELO-EHLO conversations go from servers with names which have not corresponded IP address in DNS records.

Highlighted

Hello,

 

I have that issue as well with hundreds of domains. For what I found for now, this could be related to DNSSEC issue. 

On my side I disabled DNSSEC client commands and this changes nothing.

When I dig myself, resolution is fine

 

For me that looks only postfix related...

Related Conversations
Outlook 2019 for Mac, Cannot add Shared Calendars
staceman in Office for Mac on
0 Replies
Description info sur le Get-CalendarDiagnosticAnalysis
MarkH6969 in Exchange on
0 Replies
Issues with @Mentions in Outlook
Andrew Simpson in Exchange on
0 Replies
The new Fluent design Mail Icon is here!
HotCakeX in Windows Insider Program on
1 Replies
Modify Outlook invite links
arifC in Microsoft Teams on
4 Replies