Just don't pass any command to Net::OpenSSH methods and it will run the shell. You may also like to request a tty on the remote side using tty => 1.

For instance, running the shell attached to the local stdio:

$ssh->system;
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Attaching it to a socket:

my $socket = $ssh->open2socket
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Or to a pseudo tty:

my $pty = $ssh->open2pty
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Another way to do it is to explicitly specify the shell command you want to run:

my $socket = $ssh->open2socket('/usr/sh', '-i');
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