# FreeBsd linked and disconnect network
1. linked default route and setup dns
* create route

    ifconfig <network interface> <self_ip> netmask <255.255.255.0> 
    dhclient <network interface> 

* delete route

    route del <ip> 

* setup default gateway

    route add default <default_gateway>

2. linked wifi

    use ifconfig to see if NetworkInterface is up 
    ifconfig <NetworkInterface> up 
    install net-tools first : apt install net-tools 
    wpa_passphrase [SSID_NAME] >> /etc/wpa_supplicant.conf
    wpa_supplicant -B -D <drive> -i <NetworkInterface> -c /etc/wpa_supplicant.conf
    //drive = nl80211  
    dhclient <NetworkInterface> 

3. setup static inet
* at /etc/rc.conf setup:

    hostname="freebsd12"
    ifconfig_em0="DHCP"
    ifconfig_em0_ipv6="inet6 accept_rtadv"
    sshd_enable="YES"
    # Set dumpdev to "AUTO" to enable crash dumps, "NO" to disable
    dumpdev="AUTO"