wapiti: 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/wapiti - from package: wapiti

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

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