$ dbdeployer admin set-default -h
Sets a given sandbox as default, so that it can be used with $SANDBOX_HOME/default
Usage:
  dbdeployer admin set-default sandbox_name [flags]
Flags:
      --default-sandbox-executable string   Name of the executable to run commands in the default sandbox (default "default")
  -h, --help                                help for set-default

$ dbdeployer admin set-default msb_8_0_20

$ ~/sandboxes/default status
$ ~/sandboxes/default use   # will get the `mysql` prompt
$ ~/sandboxes/default use -e 'select version()'

$ ~/sandboxes/default status_all
$ ~/sandboxes/default use_all 'select @@version, @@server_id, @@port'

$ dbdeployer admin set-default msb_8_0_20 --default-sandbox-executable=single
$ dbdeployer admin set-default repl_8_0_20 --default-sandbox-executable=repl
$ dbdeployer admin set-default group_msb_8_0_20 --default-sandbox-executable=group

$ ~/sandboxes/single status
$ ~/sandboxes/repl check_slaves
$ ~/sandboxes/group check_nodes