osgearth_backfill: 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

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/osgearth_backfill - from package: osgearth

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