Connect redis-cli in Docker to TLS Encypted ElastiCache Redis Cluster.

command.sh

# run on host...
docker run -it --entrypoint /bin/bash redis
# run inside docker...
apt-get update
apt-get install -y stunnel net-tools 
cat <<EOF > /etc/stunnel/redis-cli.conf
fips = no
setuid = root
setgid = root
pid = /var/run/stunnel.pid
debug = 7
delay = yes
options = NO_SSLv2
options = NO_SSLv3
[redis-cli]
   client = yes
   accept = 127.0.0.1:6380
   connect = <ElastiCache-ConfigurationEndpoint>
EOF

stunnel /etc/stunnel/redis-cli.conf
netstat -tulnp | grep -i stunnel
redis-cli -c --cluster-only-masters -h localhost -p 6380 -a 'PASS'

ref

https://docs.aws.amazon.com/ja_jp/AmazonElastiCache/latest/red-ug/in-transit-encryption.html
https://stackoverflow.com/questions/59492382/is-there-a-way-to-flushall-on-a-cluster-so-all-keys-from-master-and-slaves-are-d