shncat: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/shncat - from package: shntool

You may install the required package with command apt-get install {package}
Error in other languages:
shncat: bevel nie gevind nie
shncat: comandă negăsită
shncat: comando não encontrado
shncat: commande introuvable
shncat: command not found
shncat: käsku ei ole
shncat: không tìm thấy lệnh
shncat: komanda nerasta
shncat: Kommando nicht gefunden.
shncat: kommandot finns inte
shncat: komut yok
shncat: nie znaleziono polecenia
shncat: níor aimsíodh an t-ordú
shncat: no se encontró la orden
shncat: no s'ha trobat l'ordre
shncat: opdracht niet gevonden
shncat: parancs nem található
shncat: perintah tidak ditemukan
shncat: príkaz nenájdený
shncat: příkaz nenalezen
shncat: команда не найдена
shncat: командата не е открита
shncat: 命令找不到
shncat: コマンドが見つかりません