gssdp-device-sniffer: 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 CentOS possible default full paths are:

/usr/bin/gssdp-device-sniffer - from package: gssdp

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/gssdp-device-sniffer - from package: gssdp-tools

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

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