smbd: 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/sbin/smbd - from package: samba4
/usr/sbin/smbd - from package: samba

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

On Debian possible default full paths are:

/usr/sbin/smbd - from package: samba

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

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