DHCP multisubnet on Linux dhcp server

Edit config

------dhcpd.conf---------
ddns-update-style none;
default-lease-time 600;
max-lease-time 7200;
log-facility local7;

# internal subnet.
subnet 192.168.x.0 netmask 255.255.255.0 {
  range 192.168.x.90 192.168.x.150;
  option domain-name-servers 192.168.x.xx, 192.168.x.x;
  option routers 192.168.x.254;
  option subnet-mask 255.255.255.0;
  option broadcast-address 192.168.x.255;
}
# Other Subnet
subnet 192.168.2.0 netmask 255.255.255.0 {
        option subnet-mask 255.255.255.0;
        option broadcast-address 192.168.2.255;
        option routers 192.168.2.1;
        option domain-name-servers 192.168.x.xx, 192.168.x.x;
        range 192.168.2.10 192.168.2.120;
}

host computer {
  hardware ethernet 00:E0:7D:FD:04:AB;
  fixed-address 192.168.x.xx;
}


configure switch 3com 5500G-ei ให้ DHCP Relay