arckill: 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/arckill - from package: nordugrid-arc-client

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

On Debian possible default full paths are:

/usr/bin/arckill - from package: nordugrid-arc-client

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

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