---
title: README.md · master · InstitutMaupertuis
source: https://gitlab.com/InstitutMaupertuis/mattermost-old-messages/blob/master/README.md
tags:
  - IT/Tools/Gitlab
  - IT/Tools/Mattermost
---

This guide will help you delete old messages and attachments from your Mattermost Open Source edition server.

This procedure is very similar to what the [data retention](https://docs.mattermost.com/administration/data-retention.html) option of Mattermost `Enterprise Edition E20` does.

⚠ Run this at your own risk! I strongly suggest making a backup of your Mattermost directories and MySQL database before running these commands ⚠

This will be the limit date for the messages to keep (messages before this date will be deleted). Use [https://www.epochconverter.com/](https://www.epochconverter.com/) or Unix commands to generate the timestamp for your date.

*   For example: `1527811200` corresponds to the first of june 2018.
*   In Mattermost database timestamps are stored with sub seconds accuracy so you need to multiply this timestamp by 1000 for later use.

In this example we will use `1527811200000`, tweak the commands with your own timestamp.

## [](#list-old-messages-attachments)List old messages / attachments

Open the MySQL prompt on your server and issue these queries

    USE mattermost;
    SELECT * FROM FileInfo WHERE CreateAt < 1527811200000 LIMIT 10;
    SELECT * FROM Posts WHERE CreateAt < 1527811200000 LIMIT 10;

You should see information about the files / messages, this only lists 10 results.

If you get an empty set make sure you have the right timestamp (multiplied by 1000)

## [](#delete-old-messages-attachments)Delete old messages / attachments

### [](#mysql-configuration)MySQL configuration

Edit `/etc/mysql/mysql.conf.d/mysqld.cnf` and add at the end

    secure_file_priv=""

Restart MySQL

    sudo service mysql restart

This will allow us to dump the results of a query into a file on the disk.

### [](#get-a-list-of-the-attachments)Get a list of the attachments

*   Tweak the user and password corresponding to your credentials.
*   This will create a temporary directory with a file inside containing the path of each attachment that is to be removed

    #!/bin/bash
    sudo mkdir /tmp/mysqldump/
    sudo chown -R mysql:mysql /tmp/mysqldump/
    sudo rm /tmp/mysqldump/*
    mysql -u user -p'password' -D mattermost -e "SELECT Path FROM FileInfo \
    WHERE CreateAt < 1527811200000 \
    INTO OUTFILE '/tmp/mysqldump/uploaded_files.txt' \
    FIELDS TERMINATED BY ',' \
    ENCLOSED BY '' \
    LINES TERMINATED BY '\n';"

### [](#script-to-delete-the-attachments)Script to delete the attachments

Create an executable script with the following content, tweak the `/opt/mattermost/data` with your installation directory of Mattermost.

    #!/bin/bash
    input="/tmp/mysqldump/uploaded_files.txt"
    while IFS= read -r line
    do
      rm "/opt/mattermost/data/$line"
    done < "$input"

Run this script as root to delete the attachments files.

You can now delete the list of files

    sudo rm -Rf /tmp/mysqldump/

### [](#delete-the-database-entries)Delete the database entries

This will delete all the messages/attachments in the database

    mysql -u user -p'password' -D mattermost -e "DELETE FROM FileInfo WHERE CreateAt < 1527811200000;"
    mysql -u user -p'password' -D mattermost -e "DELETE FROM Posts WHERE CreateAt < 1527811200000;"

### [](#configuration-mysql)Configuration MySQL

We can now revert the MySQL configuration at `/etc/mysql/mysql.conf.d/mysqld.cnf`, comment

    #secure_file_priv=""

Restart MySQL

    sudo service mysql restart