Here I will setup fluent-bit and seq both with docker and push logs through fluent bit to to seq.
I will also show how to setup fluent bit and seq with docker.

Setup a docker network for the containers

docker network create fluent-bit_seq

Setting up Seq

At first setup a hashed password to be used

PH=$(echo 'seqPass%%' | docker run --rm -i datalust/seq config hash)

Make sure that the password variable is ok

echo $PH

Run the container

docker run --name seq -d --network fluent-bit_seq \    -p8080:80 --restart unless-stopped \    -e ACCEPT_EULA=Y -e SEQ_FIRSTRUN_ADMINPASSWORDHASH="$PH" \    datalust/seq

Now browse tolocalhost:8080 and login into Seq using username=admin password=seqPass%%

Setting up Fluent Bit

Designate a folder where you'll store the fluent bit configs. In my case the directory isD:/fluent-bit

Set the directory where fluent bit's config will come from

export sharedFolder=/var/fluent-bit_seq

Start a temporary container to copy default configs from

docker run -d --rm --name temp cr.fluentbit.io/fluent/fluent-bit

Copy the configs to your designated folder

docker cp temp:/fluent-bit/etc/ $sharedFolder

Stop the temporary container

docker stop temp

Now start fluent bit with the config folder mounted as a volume

docker run -dti --name fluent-bit --network fluent-bit_seq \    -v $sharedFolder:/fluent-bit/etc \      cr.fluentbit.io/fluent/fluent-bit

By default fluent bit is configured to output to std out. So see docker log to see what fluent bit is logging.

docker logs fluent-bit

Configuring Fluent Bit to send logs to Seq

Go to the fluent bit configuration directory and search for this section

# fluent-bit.conf[OUTPUT]    name  stdout    match *

Replace this section with this and save

# fluent-bit.conf[OUTPUT]    Name             http    Match            *    Host             seq    Port             5341    URI              /api/events/raw?clef    Format           json_lines    Json_date_key    @t    Json_date_format iso8601    Log_response_payload False

Now restart the fluent bit container for the changes to take effect.

docker restart fluent-bit

Now browse tolocalhost:8080 and login into Seq using username=admin password=seqPass%% and see that the logs are being written into Seq

Thanks for reading, Happy Tinkering :)

References

1. Github repo