IP masquerade is the name given to one type of network address translation that allows all of the hosts on a private network to use the Internet at the price of a single IP address. IP masquerading allows you to use a private (reserved) IP network address on your LAN and have your Linux-based router perform some clever, real-time translation of
Source NAT. Used to "hide" the private source IP Address (i.e.:192.168.1.109), aka masquerading. To use masquerading, a source NAT rule with action 'masquerade' should be added to the firewall configuration: /ip firewall nat add chain=srcnat action=masquerade out-interface=Public. Above example shows you how to configure NAT on a Mikrotik Indeed Masquerade is the same as Src-Nat with the automatic selection of the external address as the source address. You need to use Src-Nat only when you have more than 1 external address (e.g. a subnet) and you want to specify which address is going to be used as the source of the NATted packet. NAT Masquerade (Many-to-one) First of all lets look at configuration settings to translate a network range behind behind a single IP. set nat source rule 10 source address '192.168../16' set nat source rule 10 outbound-interface 'eth2' set nat source rule 10 protocol 'all' set nat source rule 10 translation address 'masquerade' # NAT table rules *nat :POSTROUTING ACCEPT [0:0] # Forward traffic through eth0 - Change to match you out-interface -A POSTROUTING -s 192.168.1./24 -o eth0 -j MASQUERADE # don't delete the 'COMMIT' line or these nat table rules won't # be processed COMMIT Now enable the changes by restarting ufw. $ sudo ufw disable && sudo ufw enable FORWARD
Masquerading is a special form of Source NAT where the source address is unknown at the time the rule is added to the tables in the kernel. If you want to allow hosts with private address behind your firewall to access the Internet and the external address is variable (DHCP) this is what you need to use.
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE service iptables save service iptables restart. Note: check if iptables is set to start during boot up. Or check the status of your iptables service: chkconfig -list iptables. If level 5 is on then it's ok othewise start the service at level 5 or level 2345.
Source NAT. Used to "hide" the private source IP Address (i.e.:192.168.1.109), aka masquerading. To use masquerading, a source NAT rule with action 'masquerade' should be added to the firewall configuration: /ip firewall nat add chain=srcnat action=masquerade out-interface=Public. Above example shows you how to configure NAT on a Mikrotik
Indeed Masquerade is the same as Src-Nat with the automatic selection of the external address as the source address. You need to use Src-Nat only when you have more than 1 external address (e.g. a subnet) and you want to specify which address is going to be used as the source of the NATted packet. NAT Masquerade (Many-to-one) First of all lets look at configuration settings to translate a network range behind behind a single IP. set nat source rule 10 source address '192.168../16' set nat source rule 10 outbound-interface 'eth2' set nat source rule 10 protocol 'all' set nat source rule 10 translation address 'masquerade' # NAT table rules *nat :POSTROUTING ACCEPT [0:0] # Forward traffic through eth0 - Change to match you out-interface -A POSTROUTING -s 192.168.1./24 -o eth0 -j MASQUERADE # don't delete the 'COMMIT' line or these nat table rules won't # be processed COMMIT Now enable the changes by restarting ufw. $ sudo ufw disable && sudo ufw enable FORWARD iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE service iptables save service iptables restart. Note: check if iptables is set to start during boot up. Or check the status of your iptables service: chkconfig -list iptables. If level 5 is on then it's ok othewise start the service at level 5 or level 2345. NAT vs NAPT . Network Address Translation (NAT) is the process that modifies the IP address in a header of an IP packet, while it is travelling through a routing device. NAT allows one set of IP addresses to be used for traffic within a LAN (Local Area Network) and another set of IP addresses to be used for outside traffic. Masquerading. There is a specialized case of Source NAT called masquerading: it should only be used for dynamically-assigned IP addresses, such as standard dialups (for static IP addresses, use SNAT above). sNAT y MASQUERADE: Cómo funciona el NAT en un router/firewall - Duration: 11:46. Junco TIC 2,069 views. 11:46. How to change your "Email Address (Primary Email)" in Facebook 2015 - Duration: 5:55.