Hello good day.
I have a laboratory mounted.
I have an ARRIS C3 and server in Centos 6.5,
it is happening that my cable modems are taking DHCP + TFTP + TOD but when I enter the modem cable to the wan part, I do not see that it takes an IP- a MASK- a GATEWAY- and a DNS so I do not have navigation.
but when I manually assign it in a static way the ip of my CPE block 172.21.0.1/16 to the modem this gives me access to the internet,
Question?
will be problem in the configuration of my cmts my networks are the following
172.17.0.1/24 server projection
10.50.0.1/16 cable network modem
172.21.0.1/16 network of my CPE
I use shorewall as nat
-------------------------------------------------------------------------
Configuration DHCPD
# Red Base eth0
subnet 172.17.0.0 netmask 255.255.255.0 {
	deny client-updates;
	deny unknown-clients;
	range 172.17.0.100 172.17.0.105;
	}
# Red CM-Cisco UBR 7246
subnet 10.50.0.0 netmask 255.255.0.0 {
	option subnet-mask 255.255.0.0;
	option routers 10.50.0.1;
	server-name "misa.balfate.hn";
	next-server 172.17.0.1;
	filename "noaccess.cfg";
	deny client-updates;
	deny unknown-clients;
	range dynamic-bootp 10.50.0.10 10.50.255.254;
	}
# cpe
subnet 172.21.0.0 netmask 255.255.0.0 {
	option subnet-mask 255.255.0.0;
	option routers 172.21.0.1;
	option domain-name-servers 8.8.8.8 , 8.8.4.4;
	server-name "misa.balfate.hn";
	deny client-updates;
	allow unknown-clients;
	range 172.21.0.10 172.21.255.254;
	}
-------------------------------------------------------------------------
IN MY C3
Interface Cable 1/0
ip address 10.2.0.1 255.255.255.0 // CM NETWORK
 ip address 192.168.100.65 255.255.255.224 secondary /// cpe
172.17.0.1 helper-address cable
ip route 0.0.0.0 0.0.0.0 172.17.0.1
------------------------------------------------
 FastEthernet interface 0/0
  description "Interface
 no shutdown
 ! mac-address 0013.1113.b5c5
 duplex full
 speed 100
 snmp trap link-status
 load-interval 300
 ip address 172.17.0.2 255.255.255.0
 no allow-ip-only
 management-access
 no ip directed-broadcast
 no ip source-verify
 no ip source-verify subif
 no ip l2-bg-to-bg-routing
 ip verify-ip-address-filter