In interactive mode:

ora-cmd> connect username:password@host:port/service_name;

example:

ora-cmd> connect pan:withdata@192.168.0.102:1521/orcl

In batch mode:

ora-cmd dsn="username:password@host:port/service_name"

example:

ora-cmd dsn="pan:withdata@192.168.0.102:1521/orcl"

If you want to hide password

In interactive mode:

ora-cmd> connect username@host:port/service_name;

example:

ora-cmd> connect pan@192.168.0.102:1521/orcl

In batch mode:

ora-cmd dsn="username@host:port/service_name"

example:

ora-cmd dsn="pan@192.168.0.102:1521/orcl"

Disconnect from Oracle:

ora-cmd> disconnect;