Steps to reproduce
Spin up MM Omnibus instance on Digital Ocean. (Ubuntu 20 LTS, MM 7.1.2)
Export Slack email/attachment data and convert to MM format per docs.
Attempt import of mattermost-bulk-import.zip (1.92gb)
Expected behavior
The Slack export is uploaded successfully.
This is caused by the default configuration value client_max_body_size 50M in the file /etc/nginx/conf.d/mattermost.conf. In order to permanently increase this limit, you would have to create a custom nginx.conf template as described here, but since you will only need it once for the upload, it’s safe to manually make the change and not make it permanent. To do so (let’s set it to 4G), run the following commands:
sed -i -e 's/50M/4G/' /etc/nginx/conf.d/mattermost.conf
systemctl reload nginx
You should now be able to upload the bigger file.
Upon the next mmoni reconfigure, this setting will be reverted.