lava-daemon: command not found

Have You tried accessing the binary with the full path?

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:

/usr/bin/lava-daemon - from package: lava-server

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