Email is not configured properly

[dynimighti]

the previous post have no answer. PTR6 DNS record (PTR) did not match. what is the solution?

[BrutalBirdie]

There are now many post about mail and IPv6 included PTR.
The forum search is a powerful tool

You need to set the PTR Record for your IPv6 in your hoster.

[andreasdueren]

@BrutalBirdie to be fair though I have the PTR records set up for a long time now but for some reason I keep getting these errors lately too

[jdaviescoates]

@andreasdueren I've intermittently got them a few times too.

[nebulon]

So the issue is that the PTR does not match the ipv6 or that it is intermittedly resolving to the wrong value or is there any other issue? If so more info would help to get down to it.

[Kubernetes]

I also get this error message from time to time on my Cloudron on Hetzner VPS. Usually during night and when I check in the morning the issue does not exist anymore. Maybe it is an issue with DNS Lookup?

[andreasdueren]

@nebulon This is the error show:

Email is not configured properly Yesterday
secondarytld.com

• PTR6 DNS record (PTR) did not match.
• Hostname: null
• Expected: mail.tld.com
• Actual: null

Email Status is checked every 30 minutes. See the troubleshooting docs for more information.**

[robi]

What kind of intermittent maintenance could affect this?

[jdaviescoates]

@Kubernetes said in Email is not configured properly:

I also get this error message from time to time on my Cloudron on Hetzner VPS. Usually during night and when I check in the morning the issue does not exist anymore. Maybe it is an issue with DNS Lookup?

Same (with a Hetzner dedicated server). I've had it maybe 3 or 4 times. Always around the same time in the early hours.

[nebulon]

Maybe you could contact Hetzner about this then, this is a bit out of scope for Cloudron, which only really does some sanitychecking here based on a PTR record check.

[nebulon]

Just created a Hetzner server and maybe the IPv6 PTR issue is, that the default setting is :: while Cloudron checks for ::1 (or whatever you see in the status page) After adding a second PTR for IPv6 it started to work so far at least.

[jdaviescoates]

@nebulon given the intermittent and short term nature of the issue it could just be short term network stuff happening somewhere. Mostly it's fine.

[Gengar]

@dynimighti who is your vps provider ?

Because there is a known issue in cloudron for VPS providers that are using DHCPv6, the lease will not be renewed because the traffic is not allowed on UDP port 546 (client) from port 547 (server) in Cloudron's default ip6tables ruleset. Based on RFC 8415 , this port needs to be explicitly opened for DHCPv6 to work correctly.

This issue will lead to PTR6 value = null ... simply because your ipv6 lease is not renewed and so you loose your ipv6...

You can find more information about the issue I'm talking about and a temporary fix here :
https://forum.cloudron.io/topic/13566/infomaniak-ipv6-issues/61?_=1745357068478

But if you are using Hetzner it shouldn't be the case because I did some tests and they are setting a fixed ipv6 address. It means you cannot loose your ipv6, so you shouldn't have the issue I'm talking about.

[dynimighti]

@Gengar linode

[andreasdueren]

@Gengar Hetzner dedicated and virtual

[Gengar]

@dynimighti okay so if you read the content of your netplan yaml config file you will be able to see if dhcpv6 is enabled . If yes , then you need to use the fix in the link I’ve sent before.

[Gengar]

@andreasdueren I only tried with a virtual one at hetzner so idk for the dedicated . But for virtual it’s a fixed IPv6 and I also had my ptr to null one or two times on this one but it’s temporary and very quick. I think it should be a brief interruption with their dns or something network related .

[jdaviescoates]

@Gengar said in Email is not configured properly:

I think it should be a brief interruption with their dns or something network related .

That's my current guess.

[dynimighti]

This post is deleted!

[dynimighti]

@Gengar think that worked, thanks.