rakverb2: 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 CentOS possible default full paths are:

/usr/bin/rakverb2 - from package: rakarrack

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/rakverb2 - from package: rakarrack

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

Error in other languages:
rakverb2: bevel nie gevind nie
rakverb2: comandă negăsită
rakverb2: comando não encontrado
rakverb2: commande introuvable
rakverb2: command not found
rakverb2: käsku ei ole
rakverb2: không tìm thấy lệnh
rakverb2: komanda nerasta
rakverb2: Kommando nicht gefunden.
rakverb2: kommandot finns inte
rakverb2: komut yok
rakverb2: nie znaleziono polecenia
rakverb2: níor aimsíodh an t-ordú
rakverb2: no se encontró la orden
rakverb2: no s'ha trobat l'ordre
rakverb2: opdracht niet gevonden
rakverb2: parancs nem található
rakverb2: perintah tidak ditemukan
rakverb2: príkaz nenájdený
rakverb2: příkaz nenalezen
rakverb2: команда не найдена
rakverb2: командата не е открита
rakverb2: 命令找不到
rakverb2: コマンドが見つかりません