檢視 Dhcp 的原始碼

==限制 DHCP 傾聽的網路埠==
===一般===
通常在多網路埠的系統啟動 DHCP 會去設定 /etc/sysconfig/dhcpd 來限制 DHCP 傾聽的網路裝置埠 (預設 DHCP 使用第一個埠)

<pre>
[root@localhost ~]$ cat /etc/sysconfig/dhcpd
# Command line options here
DHCPDARGS=eth0
</pre>

===CentOS / RHEL (RedHat) 7===
步驟就寫在 /etc/sysconfig/dhcpd 檔案裡面,透過 CentOS7 的 systemd 啟動 DHCP 服務時同時限制要傾聽的網路裝置.

主要的修改是在 ExecStart 最後面加入要限制傾聽的網路裝置 :ExecStart=/usr/sbin/dhcpd -f -cf /etc/dhcp/dhcpd.conf -user dhcpd -group dhcpd --no-pid '''<your_interface_name(s)>'''

<pre>
[root@localhost ~]$ cp /usr/lib/systemd/system/dhcpd.service /etc/systemd/system/
[root@localhost ~]$ vi /etc/systemd/system/dhcpd.service
[Unit]
Description=DHCPv4 Server Daemon
Documentation=man:dhcpd(8) man:dhcpd.conf(5)
Wants=network-online.target
After=network-online.target
After=time-sync.target
 
[Service]
Type=notify
ExecStart=/usr/sbin/dhcpd -f -cf /etc/dhcp/dhcpd.conf -user dhcpd -group dhcpd --no-pid ens33
 
[Install]
WantedBy=multi-user.target

</pre>

<pre>
[root@localhost ~]$ systemctl --system daemon-reload
[root@localhost ~]$ systemctl restart dhcpd.service
</pre>