uwsgi_router_access: 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/uwsgi_router_access - from package: uwsgi-plugin-router-access

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

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