tracetop: 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/tracetop - from package: libtrace-tools

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