mke2fs: 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:

/sbin/mke2fs - from package: e2fsprogs

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

On Debian possible default full paths are:

/sbin/mke2fs - from package: e2fsprogs
/usr/lib/debug/sbin/mke2fs - from package: e2fsprogs-dbg

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

Error in other languages:
mke2fs: bevel nie gevind nie
mke2fs: comandă negăsită
mke2fs: comando não encontrado
mke2fs: commande introuvable
mke2fs: command not found
mke2fs: käsku ei ole
mke2fs: không tìm thấy lệnh
mke2fs: komanda nerasta
mke2fs: Kommando nicht gefunden.
mke2fs: kommandot finns inte
mke2fs: komut yok
mke2fs: nie znaleziono polecenia
mke2fs: níor aimsíodh an t-ordú
mke2fs: no se encontró la orden
mke2fs: no s'ha trobat l'ordre
mke2fs: opdracht niet gevonden
mke2fs: parancs nem található
mke2fs: perintah tidak ditemukan
mke2fs: príkaz nenájdený
mke2fs: příkaz nenalezen
mke2fs: команда не найдена
mke2fs: командата не е открита
mke2fs: 命令找不到
mke2fs: コマンドが見つかりません