Configure EAST

The connection from EAST to WEST only requires a minor change from that configured in Basic site-to-site connection.

WEST retains its fixed IP, so no modification is required to the remote peer IP address.
EAST has a dynamic local IP, so that must change. The dhcp-interface option specifies the DHCP client interface.
EAST is also configured for dynamic DNS, in this case with service provider DynDNS. See the “Configuring Dynamic DNS” section in the Ciena Vyatta Network OS Services Configuration Guide for details on configuring a system for dynamic DNS.

To configure this connection, perform the following steps on EAST in configuration mode.

Table 1. Specify that the local IP is dynamic
Step	Command
Remove the existing local-address configuration so that doesn't conflict with the dhcp-interface configuration that will be set.	`vyatta@EAST# delete security vpn ipsec site-to-site peer 192.0.2.1 local-address [edit]`
Specify the DHCP client interface to use for the connection.	`vyatta@EAST# set security vpn ipsec site-to-site peer 192.0.2.1 dhcp-interface dp0p1p1 [edit]`
Commit the configuration.	`vyatta@EAST# commit`
View the configuration for the site-to-site connection.	`vyatta@EAST# show security vpn ipsec site-to-site peer 192.0.2.1 authentication mode pre-shared-secret pre-shared-secret test_key_1 } default-esp-group ESP-1E dhcp-interface dp0p1p1 ike-group IKE-1E tunnel 1 { local { prefix 192.168.60.0/24 } remote { prefix 192.168.40.0/24 } }`
View data plane interface dp0p1p1 address configuration. It is set to dhcp which configures it as a DHCP client. This is the setting required by dhcp-interface.	`vyatta@EAST# show interfaces dataplane dp0p1p1 address dhcp`

Display the dynamic DNS configuration on EAST:

Table 2. Display the dynamic DNS configuration
Step	Command
View the dynamic DNS configuration.	`vyatta@EAST# show service dns dynamic interface dp0p1p1 { service dyndns { host-name east.company.com login test password testpassword } }`

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