functrace: command not found

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/functrace - from package: perf-tools-unstable

You may install the required package with command apt-get install {package}

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