The problem is, Render's private services are not exposed to the internet, so how do we download the Redis data if we want to back it up, or migrate it somewhere else or whatever?
This Render article describes how we can get our hands on the data stored on attached disks using
magic_wormhole. However, the Redis Docker image runs Alpine Linux; and to install
magic_wormhole we need
apt which isn't available on this Linux distribution.
There is a workaround to install it using a long and complicated command, that I don't understand. Go to your Redis service from your Render dashboard and select the Shell tab.
Then run this command (it will take a few minutes to complete):
apk add build-base python3-dev libffi-dev openssl-dev py3-pip && pip3 install --upgrade pip && pip3 install magic-wormhole
Ensure you have
magic_wormhole installed on your local machine as well. Follow the instructions for your OS on this page.
Once the installation in both places is complete, run the following command in the Render dashboard:
wormhole send /var/lib/redis/appendonly.eof
magic_wormhole will then go away and do its magic and give you a command to run on your local machine. Run that once you have it and voila, you have the Redis data file from Render on your local machine to do with as you please!
This article was originally published on my blog