SNR S2940-8G-v2, Configuration Manual

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SNR S2940-8G-v2 Switch Configuration Guide
DHCP option 82 Configuration
that whether the DHCP client is from the network connected to Switch1 or Switch2. So, all the PC
terminals connected to Switch1 and Switch2 will get addresses from the public address pool of
the DHCP server. After the DHCP option 82 function is enabled, since the Switch3 appends the
port information of accessing Switch3 to the request message from the client, the server can tell
that whether the client is from the network of Swich1 or Swich2, and thus can allocate separate
address spaces for the two networks, to simplify the management of networks.
The following is the configuration of Switch3(MAC address is f8:f0:82:02:33:01):
Switch3(Config)#service dhcp
Switch3(Config)#ip dhcp relay information option
Switch3(Config)#ip forward-protocol udp bootps
Switch3(Config)#interface vlan 3
Switch3(Config-if-vlan3)#ip address 192.168.10.222 255.255.255.0
Switch3(Config)#interface vlan 2
Switch3(Config-if-vlan2)#ip address 192.168.102.2 255.255.255.0
Switch3(Config-if-vlan2)#ip helper 192.168.10.88
Linux ISC DHCP Server supports option 82, its configuration file /etc/dhcpd.conf is
ddns-update-style interim;
ignore client-updates;
class "Switch3Vlan2Class1" {
match if option agent.circuit-id = "Vlan2+Ethernet1/0/2"
and option agent.remote-id=f8:f0:82:02:33:01;
}
class "Switch3Vlan2Class2" {
match if option agent.circuit-id = "Vlan2+Ethernet1/0/3"
and option agent.remote-id=f8:f0:82:02:33:01;
}
subnet 192.168.102.0 netmask 255.255.255.0 {
option routers 192.168.102.2;
option subnet-mask 255.255.255.0;
option domain-name "example.com.cn";
option domain-name-servers 192.168.10.3;
authoritative;
pool {
range 192.168.102.21 192.168.102.50;
default-lease-time 86400; #24 Hours
max-lease-time 172800; #48 Hours
allow members of "Switch3Vlan2Class1";
}
pool {
range 192.168.102.51 192.168.102.80;
default-lease-time 43200; #12 Hours
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