o2cb_ctl: 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 Debian possible default full paths are:

/sbin/o2cb_ctl - from package: ocfs2-tools

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

Error in other languages:
o2cb_ctl: bevel nie gevind nie
o2cb_ctl: comandă negăsită
o2cb_ctl: comando não encontrado
o2cb_ctl: commande introuvable
o2cb_ctl: command not found
o2cb_ctl: käsku ei ole
o2cb_ctl: không tìm thấy lệnh
o2cb_ctl: komanda nerasta
o2cb_ctl: Kommando nicht gefunden.
o2cb_ctl: kommandot finns inte
o2cb_ctl: komut yok
o2cb_ctl: nie znaleziono polecenia
o2cb_ctl: níor aimsíodh an t-ordú
o2cb_ctl: no se encontró la orden
o2cb_ctl: no s'ha trobat l'ordre
o2cb_ctl: opdracht niet gevonden
o2cb_ctl: parancs nem található
o2cb_ctl: perintah tidak ditemukan
o2cb_ctl: príkaz nenájdený
o2cb_ctl: příkaz nenalezen
o2cb_ctl: команда не найдена
o2cb_ctl: командата не е открита
o2cb_ctl: 命令找不到
o2cb_ctl: コマンドが見つかりません