MX: Malformed or unexpected name server reply #1055
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Does this happen when sending or receiving email? As I understand it it is an issue about sending email and you should check the MX of the recipient address. |
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The problem appears when sending mails yes. The MX records of the recipients are good, as I tried several big companies like gmail, yahoo and some private mail servers which are set up correctly. |
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I've also found out that mailu_resolver_1 which is used as the dns server by all other containers can't actually resolve hosts itself, so pinging any site from within the resolver container does nothing. |
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Okay. Could you provide some logs from the SMTP and resolver containers?
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Alright; I've resent another email to showcase the error again smtp resolver |
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Could you try temporarily commenting out the dns settings from the SMTP service in the compose file? So we at least be certain it is related to dns. |
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Hey @kaiyou, and reconstructed the container. I then sent another email and this is the log: It seems that the DNS resolves gmail as it tries to connect to the MX entry Just for completion purposes I also tried setting the dns in the smtp to 8.8.8.8 and 8.8.4.4 and the error about the malformed MX returned. |
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Okay, so problem 1 is definitely related to the way your Docker handles external dns. Could you check your Docker version maybe? Timeouts are probably related to outgoing TCP/25 being blocked by a firewall. Could it be your local firewall? Where is the machine hosted otherwise? |
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The versions are as follows: My firewall is active but 25/tcp is allowed: Tested with telnet from my local system: I tried to remove the IP from the ports in the front service alltogether and again |
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Alriiiight Update Time: After another hours and hours of headache I found out that NONE of my docker containers could resolve any domains/urls, which led me the an error in my host config, which I fixed after a lot of looking and searching, installing dnsmasq, network-manager and so on. Long story short: It's working now, so it indeed was a problem in my HOSTs DNS rather than in my containers. The resolv.conf is now setting up correctly and all containers can resolve the names. Thanks anyway! Mailu is back in prod for me!Can thus be closed |
I'm in the same trouble... could you explain what was wrong and how did you solve it? Thanks in advance |
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Faced the same problem. I have no idea what caused it. Server had problems with free disk space and I accidently started anoter instance of nginx at 80 port. Problem was solved by fixing free disk space problem, stoppping new nginx instance, removing docker containers and recreating them with |
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Remove all images and start using docker-compose up |
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faced same issue today, but in my case is type=AAAA: Malformed or unexpected name server reply, can anyone help me to check ? this I attach my smtp and resolver logs Thanks in advance |
solving this problem with moving smtp relay to sendgrid, i don't know whats going on with my server, smtp relay trying to resolve AAAA record of smtp2go 😵 |
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I have exactly the same problem, but in my case the mailu_resolver_1 container is "unhealthy". Let me explain what I did: I duplicated the "host" VM and changed MAC address, IP address, DNS name. Everything works except the DNS resolution and thus the sending of the mails. Do you have an idea? |
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My mailu 1.7 system is working fine, but bounces mail with this error if you try to send email to a non-existent domain. (I can see it would also do that if your DNS is borked completely, as per discussions above) It was confusing enough to send me looking at tcpdump when a user reported it. postfix queries for an MX record, A record & AAAA record for the non-existent domain, all of which receive an authoritative "No such name (3)" DNS response. But it logs this bogus "malformed" error after the response to the final AAAA query. My tcpdump shows the DNS queries & responses as normal, and wireshark is pretty good at telling you about slightly bad packets. My IPv6 routing is working enough to send to GMail. So I suspect this error will only show up on mailu hosts with IPv6 enabled, but the postfix build/config seems to be fluffing the AAAA lookup. I think that's a bug to hunt down, but I'll update to 1.8 proper and see if it goes away. |
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Hi guys,
I'm having problems sending out mails via smtp. It worked a couple of days ago, now every mail I sent bounces back with a
MX: Malformed or unexpected name server replyI've looked on various search engines and all I could find was something about my MX entry in my DNS Zone file, however the DNS file hasn't changed an is still valid as this entry shows:
Tests via mxtoolbox.com also show that the Mail Server seems to be setup correctly. I can add new email adresses in the admin backend and also receive emails normally.
Things I tried so far:
I've tried different versions of Mailu (1.5, 1.6, master) with the same outcome. I tried sending mails via telnet which also gives the same outcome.
I also came across issue #26 where a workaround within the
/etc/resolv.confis suggested but that didn't work either.I recreated the docker containers with docker-compose and tried setting dns server manually for
mailu_smtp_1.I telnetted into the SMTP port and tried sending a message from there, with the same outcome
I put my email adress in thunderbird (which automatically detected the necessary ports) and tried to send a mail from there, with the same outcome.
I disabled ufw for some time as well as flushed my ip tables.
I can't seem to figure out what the problem is here. Has anyone experienced something similar and know an answer to this?
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