olsrd: 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/sbin/olsrd - from package: olsrd

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