Email issues with mail1 and hetzner

witt · April 24, 2025, 3:53pm

Hello Community,

I have an Nethserver v8 installed and an nethsecurity v8 installed.

my current goal is that i want to get emails throught Hetzner(outside) into my Nethserver mail1 application, i have several ports open like 25,143 and 587, ive put dns entries in hetzner with mail.xxxx.xx which is configured in my mail1.

I have a webtop running where i currently cant send, nor receive emails, UNLESS i create the specific hetzner email, then i can send emails from my webtop, but thats not my goal i want to do everything from inside my nethserver.

any help is appreciated i can send logs or test if u tell me where, thanks alot for your time!

mrmarkuz · April 26, 2025, 9:46pm

You would need to setup at least an A wildcard record “*.domain.tld” pointing to the NS8 IP and an MX record to declare your mailserver. Check out this wiki page for more information about needed DNS records for mail.

You can check your mail server and the DNS records at https://mxtoolbox.com/

witt · April 28, 2025, 8:15am

I got an A record on Hetzner with mail.xx and my public ip and webtop.xx on my public IP,

when i go to my public IP i see this error message right here:

OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ STARTTLS LOGINDISABLED] Dovecot ready.
GET BAD Error in IMAP command received by server.
Host: BAD Error in IMAP command received by server.
BYE Too many invalid IMAP commands.

ON my Port Forwards in my Firewall i have 25,143,587, 443, 80, 110, 993 and 995.
An MX is also configured on my Hetzner DNS to mail.xxx

robb · April 28, 2025, 8:43am

As Markus stated, you also need to point an MX record to the IP address of your NS8 mailinstance

you mentioned you did that, so please start troubleshooting mail traffic using a tool like mxtoolbox

does your mail / MX record resolve from the outside?

Khulisa · May 6, 2025, 9:22am

To add to what Rob said, make sure all your external DNS is working with mxtoolbox or similar. If that all checks out I would suggest looking at the second line in your error message.

mrmarkuz · May 6, 2025, 12:01pm

It seems you’re using telnet to connect to port 143 which doesn’t work as you need to use STARTTLS to enable login or you connect to port 993 using TLS

witt · May 14, 2025, 12:10pm

i fixxed it now by using the mxtool website and now ive got everything authenticated on there, my problem now is that i can send and receive emails, but only from gmails right now, no other email services…

mrmarkuz · May 15, 2025, 7:40am

That’s interesting as usually mailing is working and gmail needs special care like working SPF, DKIM etc…

Just to exclude missing IPv4/IPv6 issues, could you please check /etc/hosts if the localhost entries (127.0.0.1, ::1) are correct, see also One NethServer environment cannot send email - #6 by mrmarkuz

Could you please share the mail app logs when sending/receving is not working to get the error?

Did you set right identities for sending with other accounts than gmail? For example you can’t send via gmail using the mail address “user@outlook.com”.

witt · May 15, 2025, 9:33am

127.0.0.1 localhost

commented by set-fqdn #127.0.1.1

The following lines are desirable for IPv6 capable hosts

::1 localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
127.0.0.1 cluster-leader
10.5.4.1 cluster-localnode
127.0.1.1 z1.gradi-consulting.de z1

This is the mail system at host mail.gradi-consulting.de.

I’m sorry to have to inform you that your message could not
be delivered to one or more recipients. It’s attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

               The mail system

xxx@witt-solutions.de: host www220.your-server.de[188.40.30.77] said:
550-Verification failed for xxx@gradi-consulting.de 550-Unrouteable
address 550 Sender verify failed (in reply to MAIL FROM command)

mrmarkuz · May 15, 2025, 9:57am

It seems the Hetzner smarthost www220.your-server.de is still used.
Please check the Relay settings in the cluster-admin, there should be no rule:

Maybe helpful info:

Google AI recommendations

The “550-Unrouteable address 550 Sender verify failed” error indicates that an email was rejected because either the recipient’s email server couldn’t find the route to the recipient’s address or the sender’s email address couldn’t be verified. This error can be caused by issues on either the sender’s or recipient’s end.

Possible causes and solutions:

Unrouteable address (Recipient side):

Incorrect or invalid email address:

Double-check the recipient’s email address for typos or incorrect formatting.

Recipient’s email server issues:

The recipient’s email server might be temporarily down or experiencing technical difficulties.

DNS configuration problems:

The recipient’s domain might have issues with their DNS records, making it difficult for the sender’s mail server to find the correct email server.

Recipient’s server blocking:

The recipient’s email server might be blocking the sender’s IP address or domain, potentially due to spam policies.

Sender verify failed (Sender side):

Incorrect sender address:

The sender’s email address might be invalid or improperly formatted.

Missing or incorrect DNS records:

The sender’s domain might have issues with their MX records, preventing the recipient’s mail server from finding the correct email server.

Sender’s mail server configuration:

The sender’s mail server might have a misconfiguration that prevents it from verifying the sender’s address.

Spam filtering:

The recipient’s mail server might be rejecting the email due to sender verification or other anti-spam measures.

Troubleshooting steps:

Verify the recipient’s email address: Ensure the address is correctly spelled and formatted.
Check the recipient’s email server status: See if the recipient’s email server is online and functioning correctly.
Check DNS records: Verify that both the sender’s and recipient’s domains have correctly configured MX records.
Contact the recipient’s email administrator: If you’ve exhausted other troubleshooting steps, contact the recipient’s email administrator for assistance.
Check sender’s mail server configuration: Review the sender’s mail server configuration for any errors or misconfigurations.
Review email routing settings: Ensure that the email routing settings are correctly configured on both the sender’s and recipient’s mail servers.