fallocate: 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/fallocate - from package: util-linux-ng

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

On Debian possible default full paths are:

/usr/bin/fallocate - from package: util-linux

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

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