How to make dhclient send hostname to DHCP server

My Arch Linux recently switched from dhcpcd to dhclient as the DHCP client. The DHCP server isn’t assigning a FQDN to this client and it turns out that dhclient isn’t telling the server what’s the client’s hostname. Solution: Create config file /etc/dhclient.conf with content: send host-name = gethostname();

How to check if promiscuous mode is enabled on network interface in Linux

$ netstat -i Look under the last column “Flg” for value “P”. If it’s there, it means promiscuous mode is enabled for that network interface. Is the flag really P and not M? Here’s a quick test. Check existing active flags: [root@localhost ~]# netstat -i Kernel Interface table Iface       MTU Met    RX-OK RX-ERR RX-DRP RX-OVR    […]