ESR Series Routers Operation Manual
47
Objective 2
: Configure access for users in LAN 21.12.2.0/24 to public network using Source NAT
function without the firewall. Public network address range for SNAT 200.10.0.100-200.10.0.249.
Fig. 7.6
—
Network structure
Solution:
Begin configuration with network interface configuration and disabling the firewall:
esr(config)#
interface gigabitethernet 1/0/1
esr(config-if-gi)#
ip address 21.12.2.1/24
esr(config-if-gi)#
ip firewall disable
esr(config-if-gi)#
exit
esr(config)#
interface tengigabitethernet 1/0/1
esr(config-if-te)#
ip address 200.10.0.99/24
esr(config-if-te)#
ip firewall disable
esr(config-if-te)#
exit
For SNAT function configuration, create 'LOCAL_NET' LAN address profile that includes addresses
which are allowed to access the public network and 'PUBLIC_POOL' public network address profile.
esr(config)#
object-group network LOCAL_NET
esr(config-object-group-network)#
ip address-range 21.12.2.2-21.12.2.254
esr(config-object-group-network)#
exit
esr(config)#
object-group network PUBLIC_POOL
esr(config-object-group-network)#
ip address-range 200.10.0.100-200.10.0.249
esr(config-object-group-network)#
exit
Configure SNAT service.
First step is to create public network address pool for use with SNAT:
esr(config)#
nat source
esr(config-snat)#
pool TRANSLATE_ADDRESS
esr(config-snat-pool)#
ip address-range 200.10.0.100-200.10.0.249
esr(config-snat-pool)#
exit
Second step is to create SNAT rule set. In the set attributes, specify that the rules are applying only
to packets transferred to public network through te1/0/1 port. Rules include a check which ensures that
data source address belongs to 'LOCAL_NET' pool:
esr(config-snat)#
ruleset SNAT
esr(config-snat-ruleset)#
to interface te1/0/1
esr(config-snat-ruleset)#
rule 1
esr(config-snat-rule)#
match source-address LOCAL_NET
esr(config-snat-rule)#
match destination-address any
esr(config-snat-rule)#
match protocol any
esr(config-snat-rule)#
action source-nat pool TRANSLATE_ADDRESS
esr(config-snat-rule)#
enable
esr(config-snat-rule)#
exit
esr(config-snat-ruleset)#
exit