gnunet-peerinfo: 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/gnunet-peerinfo - from package: gnunet

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

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