grail-test-atomic: command not found

Have You tried accessing the binary with the full path?

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 Debian possible default full paths are:

/usr/bin/grail-test-atomic - from package: grail-tools

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