obus-gen-server: 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/obus-gen-server - from package: libobus-ocaml-bin

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