Need a little help troubleshooting

Brandon

Hi everyone I’m fairly new to Mailcow but it’s been working good for an awhile now receiving and sending emails with no issues then It stopped receiving emails all of a sudden. It’s probably something simple or maybe not. I’m honestly not sure where to start looking. I look in the logs but I really don’t understand what it means. If anyone is willing to help I would appreciate it.

Currently I can send emails but when trying to receive I get nothing. No email failed notice on the sender email either.

When I look at the postfix log on the webui I get warning: TLS library problem: error 0A00006C:SSL routines bad key share…/ssl/statem/extensions_srvc.c:663:

I am using a smtp relay and is self hosted at home.

Also has anyone used the techs on fiverr to troubleshoot and fix my Mailcow or if anyone has any recommendations that would be awesome.

ETNyx

First of all about Fiverr, you do what you think is the best, but I would NEVER let 20$ stranger into my server,..

About your problem,..

check your connection from outside [1], [2]
self hosted on home connection? Make sure you ISP i honest and does not change your network, does not poke into your packets
both sending and receiving parts are updated systems?
all containers ale healthy?
check your disk space?

If you lack knowledge, start feeding your logs into AI (cautiously) and talk about it whit it. At least it can point something more concrete for us (This one does not tell us much).

Brandon

ETNyx He’s gonna charge me $80 and has pretty good reviews, but I was skeptical about it as I didn’t want anyone in as well have no idea how to track what they are doing?

What logs should I start with? I been looking at the Web ui logs. If I post some logs here which command for the logs should I use?

And also If I just wanted to start over.
How can I backup my mailcow mailboxes?

What command should I use to wipe everything and does this require a new install of Ubuntu?

ETNyx

Before everything i would try to chat about your problem using AI. Use OpenAI or Claude (those are best today). Describe you problem, your findings, question it what it need from you and do not forget to mention it’s Mailcow you are using.

Logs
Backup (basiccaly it make it fresh for you, but i doubt you need this,…)

Brandon

ETNyx Thank you for that. I was playing around with that MX tool you sent. My ip was clean but now Spamhaus ZEN has my ip blocked for PBL. Do you think this my problem?

ETNyx

Well it’s a problem but i would guess it’s different one. Did you try that AI chat?

Brandon

ETNyx LOL Yes I have never used AI. I used the open ai you recommended and gave it my logs and AI fixed it. Walked me through it like I had an instructor. Had to make a small change in Mailcow.conf as well. Basically Mailcow postfix and my smtp relay was having a fight with each other at least that’s how AI explained it to me lol. It told me to remove ufw and disable postfix and it fixed it. Also has a little issue with the ssl certificate with let’s encrypt and it fixed that too. It also successfully helped me remove my ip from that backlist.

Very surprised. Never thought it was this good.

I appreciate it and saved me from starting all over and or spending $$ for a pro to fix something I don’t understand.
I did like how it explained to me what each thing is actually supposed to do, so I am learning about it as well.
I will definitely use that AI again for my Mailcow.

Interestingly enough I decided to take my shot with my ISP and see if they can open my smtp outbound port 25 and they removed the restrictions. But AI told me to continue using my smtp relay and it would bypass the PTR that I don’t have because.

What your opinion, Do You think it’s worth it for me to try to get them to add a PTR for my server or would this just stir up issues with my ISP? I heard I can buy a static IP block but idk if this would help. Currently my ip has not changed in the 6 years I been with them. I currently have my router forwarding ports to my server and opnsense running in between my router and server for security.

ETNyx

I would suggest to read through mailcow docs thoroughly

it state you should not use ufw (firewalld and others) on your host
it state that you should not have colliding apps on your hosts (as postfix)
let’s encrypt issue was most-likely due to ufw (also stated in docs)

Yes, AI is very helpful, but you still need to challenge it, if it does not know answer it often pretend it know it, sometimes if you tell him read this logs it read just a part, but it will state it read it whole and so it can miss the problem,… But it’s usually much smarter than me due to large knowledge base it contains and worth using now.

Brandon Do You think it’s worth it for me to try to get them to add a PTR for my server or would this just stir up issues with my ISP?

I would stay using relay. IP from home ISP are often on “lists” as “not reliable” and are penalized just by that (more than IP’s whole range. (also about this, if your relay is behind your isp just like MC, there is no point of using relay)

Kevo

Brandon

I like having my own static IP and not needing a relay personally, but whether or not this is a viable solution for you would largely depend on your particular ISP and their policies. Most either have a “business” plan or charge additional for a static IP block and will be able to set up a PTR for you if you are on a static block or business plan, but I would just talk to them and see how they handle such a situation. Sometimes even when you are on a business plan it’s difficult to get to the person that knows how to update the PTR records.