rolllog: 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/rolllog - from package: dnssec-tools

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

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