swapspace: 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 Debian possible default full paths are:

/usr/sbin/swapspace - from package: swapspace

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

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