Email sending broken after updating to 8.2.x (due to IPv6 issues)

[nebulon]

If you use wildcard DNS then you also have to setup the AAAA (ipv6) wildcard DNS record on your own

[avatar1024]

@nebulon thank you, I thought so but wasn't sure. I've done that and it first glance it seems to have solved both the app install and email bounce issue!

I'll reactivate IPv6 and try those settings on the two other servers and see if all email delivery problem also disappear.

Do I need to also create a AAAA record for the bare domain?

[jdaviescoates]

@girish said in Email sending broken after updating to 8.2.x (due to IPv6 issues):

To fix the situation, you simply have to set IPv6 PTR record .

And enable IPv6 in Network settings, and then (for good measure) Sync DNS in Domains

[privsec]

Sooo.... Assume that someone doesn't do this every day.

What does one have to do to get email sending to work again?
I'm using netcup and this is the IPV6 screen

[jdaviescoates]

@privsec could be wrong, but it doesn't look like there is anywhere for you to and rDNS/ PTR/ reverse dns record for your IPv6. I'd contact netcup support.

ah, seems you should be able to do so but they've just got a crappy unclear UI

https://helpcenter.netcup.com/en/wiki/server/network-server

I'd try whacking your mail url (my
cloudron.domain unless you've changed it) into that empty field with the disk image to the right and then clicking the disk

Then check if it worked with

dig -x <your ipv6 address> +short

[avatar1024]

@privsec you can do it. In the bottom section (i.e the IPv6 section), enter the full IPv6 address in the field on the left and the PTR record (my.yourdomain.xx) on the right, press save.

You get the full IPv6 address with the command Girish gave above (or by activating IPv6 in Cloudron settings it will show the IPv6 address automatically detected).

[privsec]

OK, I grabbed the IPv6 addy from cloudron and pasted it in netcup and used the same rDNS name addy for IPv4.

Nwtcup now says to wait 48 hrs

[avatar1024]

@privsec yeah netcup says that but it may only takes a few minutes. You can check your PTR record propagated in various ways, for example:

• https://toolbox.googleapps.com/apps/dig/#PTR/
• https://www.whatsmydns.net/#PTR

[potemkin_ai]

Got the same issue again, with Outlook servers again. IPv6 is disabled on Cloudron settings and on OS level.

[potemkin_ai]

fixed by removing IPv6 IP address from Hetzner completely and cleaning up old AAA entries from DNS - they seems like confused Outlook servers.

[privsec]

I set this up and it worked on netcup for about a week.

It’s giving me Al the error again about gmails ipv6 not being set up correctly.

Is there an in-depth how to guide to correcting this on netcup?

[joseph]

@privsec if you update to 8.2.4, the ipv6 check is already in place. Check the status tab after update. What does it say?

[jdaviescoates]

@privsec not netcup specific but the most in depth guide is this post by @avatar1024 :

https://forum.cloudron.io/topic/13072/gmail-ipv6-anyone-else-with-this-experience/22?_=1738857946551

[sponch]

Also got massive problems sending mails for 2 days now. Possible that 8.2.4 was released that day?

[jdaviescoates]

@sponch have you sorted out your IPv6 stuff?

[sponch]

Yes. Worked well after doing so for some days. Then „out of the blue“ sending not possible anymore on both of my instances.
„Email not configured properly“ errors in notifications when I go to email-overview page it takes 30-40 seconds until the domains get green. All values are set correctly for every single domain…
Log says: Delivery failure, will retry in 65536s.. DNS lookup failure: Error: queryMx ESERVFAIL

[joseph]

@sponch they might be old emails. You can just delete the old mail queue (to check if these are fresh failures) from /home/yellowtent/boxdata/mail/haraka-queue/ (files inside it). Restart mail container after deleting files.

[sponch]

will try that.
Just found that issue on Hetzner: can that be the reason??
Due to a missing DKIM signature (DomainKey), external mail servers reject your e-mails as spam. For this reason, we have activated DKIM for your domains.

If you use our DNS servers for these domains, the DKIM record has been automatically set in the DNS. If you use external DNS servers for these domains, you must also store the displayed DNS record there accordingly. To do this, open the ‘Products’ tab, select the domain in question and click on ‘Advanced settings’ under the menu items ‘E-Mail; DKIM / SPF / DMARC’.

[sponch]

@Joseph did that an deleted 15 Mails (these were all test mails I tried to send) an restarted mail. No difference still have the same problems..

[jdaviescoates]

@sponch said in Email sending broken after updating to 8.2.x (due to IPv6 issues):

Just found that issue on Hetzner: can that be the reason??

Could be. Have you hit resync dns after enabling and doing all the ipv6 stuff? I think that should auto generate this stuff for you (presuming you're using a supported DNS provider)