R2rpm: 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/R2rpm - from package: R2spec

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

Error in other languages:
R2rpm: bevel nie gevind nie
R2rpm: comandă negăsită
R2rpm: comando não encontrado
R2rpm: commande introuvable
R2rpm: command not found
R2rpm: käsku ei ole
R2rpm: không tìm thấy lệnh
R2rpm: komanda nerasta
R2rpm: Kommando nicht gefunden.
R2rpm: kommandot finns inte
R2rpm: komut yok
R2rpm: nie znaleziono polecenia
R2rpm: níor aimsíodh an t-ordú
R2rpm: no se encontró la orden
R2rpm: no s'ha trobat l'ordre
R2rpm: opdracht niet gevonden
R2rpm: parancs nem található
R2rpm: perintah tidak ditemukan
R2rpm: príkaz nenájdený
R2rpm: příkaz nenalezen
R2rpm: команда не найдена
R2rpm: командата не е открита
R2rpm: 命令找不到
R2rpm: コマンドが見つかりません