tonedebug: 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/lib/debug/usr/bin/tonedebug - from package: libvpb-dbg
/usr/bin/tonedebug - from package: vpb-utils

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