How to read delivery logs in poste.io (free version / selfhosted)

2025-02-14 18:11 CEST

Recently one of my customers had an issue with emails not being delivered to office365 from the selfhosted
poste.io server - free version, of course ...

Go into your docker container of your poste.io


    docker exec -ti mailserver bash

Go into the directory which includes the delivery logs:


    cd /var/log/delivery

In this directory you'll find for each day a delivery log. If you want to check the log for today (2025-02-13), then execute the following command:


    cat 2025-02-13-total

Example output of a log entry / sent mail:


    2025-02-13T16:10:03.306Z [21FEB981-9069-494C-BEE2-403546F379C0.1] 11.22.33.44:33270%some-dns.name
    (monitor@email-address.org)  ->  -
            [][<21FEB981-9069-494C-BEE2-403546F379C0.1@mail.server.com>] 250 Message Queued
                (21FEB981-9069-494C-BEE2-403546F379C0.1)

I changed the ips, dns names and mail addresses, of course. As first indicator you'll find the message of your server "250 Message Queued", which means your mailserver received the mail and will try to send it later.

From the entry you'll receive an ID for the email in this case 21FEB981-9069-494C-BEE2-403546F379C0.1. With this ID you're now able to get more informations about the delivery.

Within the log folder you'll find the folders conn, del and tx. In this folders you must go into subfolders to find your email by the id. The delivery of the email with the id 21FEB... begins with an 2 and after the 2 a 1 follows. So we need to get into conn/2/1/IDOFTHEMAIL and we get the complete connection log from the server to your mailserver.

Same as del. Within the log del/2/1/21FEB981-9069-494C-BEE2-403546F379C0.1 you'll get the whole delivery information from your mailserver to the receiving mailserver.

Same as tx. Within the log tx/2/1/21FEB981-9069-494C-BEE2-403546F379C0.1 you'll get additional log informations for the email.

I hope this helps you. I searched quite a while to find this information.