R2spec: 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/R2spec - from package: R2spec

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

Error in other languages:
R2spec: bevel nie gevind nie
R2spec: comandă negăsită
R2spec: comando não encontrado
R2spec: commande introuvable
R2spec: command not found
R2spec: käsku ei ole
R2spec: không tìm thấy lệnh
R2spec: komanda nerasta
R2spec: Kommando nicht gefunden.
R2spec: kommandot finns inte
R2spec: komut yok
R2spec: nie znaleziono polecenia
R2spec: níor aimsíodh an t-ordú
R2spec: no se encontró la orden
R2spec: no s'ha trobat l'ordre
R2spec: opdracht niet gevonden
R2spec: parancs nem található
R2spec: perintah tidak ditemukan
R2spec: príkaz nenájdený
R2spec: příkaz nenalezen
R2spec: команда не найдена
R2spec: командата не е открита
R2spec: 命令找不到
R2spec: コマンドが見つかりません