resolvertest: 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/bin/resolvertest - from package: shibboleth-sp2-utils

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

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