Hi TD_asilva
Option #1 (doing scp/sftp from solace cli to a scp/sftp host): Please give a copy what you have tried, what error you have seen.
a simple
sftp blakeks@sftphost.com
should be sufficent. It will ask for password.
Option #2 (doing sftp from outside to solace cli): Please give a copy what you have tried. Just guessing: Which scp/sftp/ssh-port have you used ? What was your command line ? (just to be sure: To use scp with a different port, you have to use something like
scp -P 2222 blakeks@solace.ip (and that’s a capital “P”)
Option #3 (docker cp) and option #4 (mapped volumes): In both cases, you have maybe the same issue 
Inside the docker container, the path is named “/usr/sw/jail/certs”.
Inside the solace cli, this path is mapped to “/certs”
The mapping between docker container and docker host says, this path is mapped to: “/var/lib/docker/volumes/jail/_data/certs”
With that in mind, you should do:
docker cp xxx.cert solace:/usr/sw/jail/cert
OR
(on your linux shell): cp xxx.cert /var/lib/docker/volumes/jail/_data/certs/