How to fix the "ValueError: No value exists in Redis for process ID of: xxx" error

This error usually happens with Docker setups on a VPS. There could be a few reasons for this error. I'll show you how to debug it and fix common cases.

To see why it's happening in your case, you need to look at your Redis logs by running:

# redis is the default name for the Redis container in Jesse's docker setup
docker logs redis

Failed opening the RDB file backup.db (in server root dir /etc) for saving: Permission denied

If you see this line in your logs, it's related to a permission issue. To fix it, in your docker-compose.yml file, after this line:

container_name: redis

Add this:

command: redis-server --save "" --appendonly no

For changes to take effect, you need to update and rebuild the redis container. Inside your project's docker directory, run:

# stop running containers
docker-compose down
# remove the redis container
docker rm redis
# just in case to make sure you have the latest image
docker-compose pull
# rebuild the redis container
docker-compose up -d

Possible SECURITY ATTACK detected. It looks like somebody is sending POST or Host: commands to Redis. This is likely due to an attacker attempting to use Cross Protocol Scripting to compromise your Redis instance. Connection aborted.

If you see this line in your logs, it's related to a security issue. Somebody (or someone's bot) is sending requests to your server's Redis instance. It's essential to always set up a firewall to make sure only you can access your remote server.

To do that, please read this guide on our documentation about how to set up a firewall for Jesse.

Other

If none of the above is your case, don't hesitate to get in touch with us with the output of docker logs redis so we can help you.