oLschema2ldif: 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/oLschema2ldif - from package: samba4-client

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

On Debian possible default full paths are:

/usr/bin/oLschema2ldif - from package: samba

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

Error in other languages:
oLschema2ldif: bevel nie gevind nie
oLschema2ldif: comandă negăsită
oLschema2ldif: comando não encontrado
oLschema2ldif: commande introuvable
oLschema2ldif: command not found
oLschema2ldif: käsku ei ole
oLschema2ldif: không tìm thấy lệnh
oLschema2ldif: komanda nerasta
oLschema2ldif: Kommando nicht gefunden.
oLschema2ldif: kommandot finns inte
oLschema2ldif: komut yok
oLschema2ldif: nie znaleziono polecenia
oLschema2ldif: níor aimsíodh an t-ordú
oLschema2ldif: no se encontró la orden
oLschema2ldif: no s'ha trobat l'ordre
oLschema2ldif: opdracht niet gevonden
oLschema2ldif: parancs nem található
oLschema2ldif: perintah tidak ditemukan
oLschema2ldif: príkaz nenájdený
oLschema2ldif: příkaz nenalezen
oLschema2ldif: команда не найдена
oLschema2ldif: командата не е открита
oLschema2ldif: 命令找不到
oLschema2ldif: コマンドが見つかりません