12When you configure a gat eway address for a P PP address pool, follow theserestrictions andguidelines:• If you also specify an IP address for an interface, the interface uses its own IP address toperform IPCP negotiation.• You can specify only one gateway address for a PPP address pool. Different PPP addresspools must have different gateway addresses (different combinations of ip-addressand vpn-instance-name).• You can specify any gateway address for a PPP address pool.Examples# Specify gateway address 1.1.1.1 and VPN instance test for PPP address pool aaa. system-view[Sysname] ip pool aaa gateway 1.1.1.1 vpn-instance testRelated commandsip poollink-protocol pppUse link-protocol ppp to enable PPP encapsulation on an interface.Syntaxlink-protocol pppDefaultPPP encapsulation is enabled on all interfaces except Ethernet, VLAN, and ATM interfaces.ViewsInterface viewPredefined user rolesnetwork-adminExamples# Enable PPP encapsulation on Serial 2/1/0. system-view[Sysname] interface serial 2/1/0[Sysname-Serial2/1/0] link-protocol pppnas-port-typeUse nas-port-type to configure the nas-port-type attribute on a VT interface.Use undo nas-port-type to restore the default.Syntaxnas-port-type { 802.11 | adsl-cap | adsl-dmt | async | cable | ethernet | g.3-fax | hdlc | idsl| isdn-async-v110 | isdn-async-v120 | isdn-sync | piafs | sdsl | sync | virtual | wireless-other| x.25 | x.75 | xdsl }undo nas-port-typeDefaultThe nas-port-type attribute is determined by the service type and link type of the PPP user, as shownin Table 5.
