Example for Configuring an LTE Cellular Interface as the Backup Interface to Connect to the Internet
Networking Requirements
As shown in Figure 12-12, Router is the egress gateway of the enterprise, and the VDSL interface functions as the primary interface to connect to the Internet.
To ensure reliable access, the enterprise requires that the LTE cellular interface should function as a backup interface to connect enterprise users to the Internet when the primary interface is faulty.
The following figure shows only the access-side networking. Deploy devices on the aggregation and core networks according to site requirements.
Configuration Roadmap
- Configure the enterprise intranet and configure the Router as the enterprise's egress gateway to assign IP addresses to enterprise intranet users.
- Configure the VDSL interface as the uplink primary interface.
- Configure the LTE cellular interface as the uplink backup interface.
- Configure a default route so that traffic from the enterprise intranet is transmitted to the Internet through the VDSL or LTE cellular interface.
Procedure
- Configure the enterprise intranet.
<Huawei> system-view [Huawei] sysname Router [Router] vlan 10 [Router-vlan10] quit [Router] dhcp enable [Router] interface vlanif 10 [Router-Vlanif10] ip address 192.168.100.1 255.255.255.0 [Router-Vlanif10] dhcp select global [Router-Vlanif10] quit [Router] ip pool lan [Router-ip-pool-lan] gateway-list 192.168.100.1 [Router-ip-pool-lan] network 192.168.100.0 mask 24 [Router-ip-pool-lan] quit [Router] interface ethernet 2/0/0 [Router-Ethernet2/0/0] port link-type hybrid [Router-Ethernet2/0/0] port hybrid pvid vlan 10 [Router-Ethernet2/0/0] port hybrid untagged vlan 10 [Router-Ethernet2/0/0] quit
- Configure the VDSL interface as the uplink primary interface.
This example only describes the configuration of the uplink primary interface. For details about other uplink devices, see the related manuals.
[Router] acl number 3002 [Router-acl-adv-3002] rule 5 permit ip source 192.168.100.0 0.0.0.255 [Router-acl-adv-3002] quit [Router] interface virtual-template 10 [Router-Virtual-Template10] ip address ppp-negotiate [Router-Virtual-Template10] nat outbound 3002 [Router-Virtual-Template10] quit [Router] interface atm 1/0/0 [Router-Atm1/0/0] pvc voip 1/35 [Router-atm-pvc-Atm1/0/0-1/35-voip] map ppp virtual-template 10 [Router-atm-pvc-Atm1/0/0-1/35-voip] quit [Router-Atm1/0/0] standby interface cellular 0/0/0 [Router-Atm1/0/0] quit
- Configure the LTE cellular interface as the uplink backup interface.
# In this example, set the dialer number to *99#.
# Use the APN specified by the carrier. In this example, set the APN to ltenet.
Before configuring the backup interface, ensure that the LTE data cards and SIM cards are available.
This example only describes the configuration of the uplink backup interface. For details about other uplink devices, see the related manuals.
[Router] dialer-rule [Router-dialer-rule] dialer-rule 1 ip permit [Router-dialer-rule] quit [Router] apn profile ltenet [Router-apn-profile-ltenet] quit [Router] interface cellular 0/0/0 [Router-Cellular0/0/0] ip address negotiate [Router-Cellular0/0/0] dialer enable-circular [Router-Cellular0/0/0] dialer-group 1 [Router-Cellular0/0/0] dialer timer idle 50 [Router-Cellular0/0/0] dialer number *99# autodial [Router-Cellular0/0/0] nat outbound 3002 [Router-Cellular0/0/0] mode lte auto [Router-Cellular0/0/0] apn-profile ltenet [Router-Cellular0/0/0] shutdown [Router-Cellular0/0/0] undo shutdown [Router-Cellular0/0/0] quit
- Configure a default route.
[Router] ip route-static 0.0.0.0 0.0.0.0 virtual-template 10 preference 40 [Router] ip route-static 0.0.0.0 0.0.0.0 cellular 0/0/0 preference 80
- Verify the configuration.
# After the configuration is complete, run the display standby state command on the Router to check the status of the primary and backup interfaces. The command output shows that ATM1/0/0 is in Up state and Cellular0/0/0 is in Standby state.
[Router] display standby state Interface Interfacestate Backupstate Backupflag Pri Loadstate ATM1/0/0 UP MUP MU Cellular0/0/0 STANDBY STANDBY BU 0 Backup-flag meaning: M---MAIN B---BACKUP V---MOVED U---USED D---LOAD P---PULLED ---------------------------------------------------------------------------- Below is track BFD information: Bfd-Name Bfd-State BackupInterface State ---------------------------------------------------------------------------- Below is track IP route information: Destination/Mask Route-State BackupInterface State ---------------------------------------------------------------------------- Below is track NQA Information: Instance Name BackupInterface State# Run the shutdown command on ATM1/0/0 to simulate a link fault. Run the display standby state command on the Router to check the status of the primary and backup interfaces. The command output shows that ATM1/0/0 is in Down state and Cellular0/0/0 is in Up state, indicating that the backup interface has started.
[Router-Atm1/0/0] shutdown [Router-Atm1/0/0] quit [RouterA] display standby state Interface Interfacestate Backupstate Backupflag Pri Loadstate ATM1/0/0 DOWN MDOWN MU Cellular0/0/0 UP UP BU 0 Backup-flag meaning: M---MAIN B---BACKUP V---MOVED U---USED D---LOAD P---PULLED ---------------------------------------------------------------------------- Below is track BFD information: Bfd-Name Bfd-State BackupInterface State ---------------------------------------------------------------------------- Below is track IP route information: Destination/Mask Route-State BackupInterface State ---------------------------------------------------------------------------- Below is track NQA Information: Instance Name BackupInterface State
Configuration Files
Configuration file of the Router
# sysname Router # vlan batch 10 # dhcp enable # acl number 3002 rule 5 permit ip source 192.168.100.0 0.0.0.255 # apn profile ltenet # ip pool lan gateway-list 192.168.100.1 network 192.168.100.0 mask 255.255.255.0 # interface Vlanif10 ip address 192.168.100.1 255.255.255.0 dhcp select global # interface Ethernet2/0/0 port hybrid pvid vlan 10 port hybrid untagged vlan 10 # interface Cellular0/0/0 dialer enable-circular dialer-group 1 apn-profile ltenet dialer timer idle 50 dialer number *99# autodial nat outbound 3002 modem auto-recovery dial action modem-rebootfail-times 128 modem auto-recovery services-unavailable action modem-reboot test-times 0 interval 3600 ip address negotiate # interface Atm1/0/0 pvc voip 1/35 map ppp Virtual-Template10 standby interface Cellular0/0/0 # interface Virtual-Template10 ip address ppp-negotiate nat outbound 3002 # dialer-rule dialer-rule 1 ip permit # ip route-static 0.0.0.0 0.0.0.0 Virtual-template10 preference 40 ip route-static 0.0.0.0 0.0.0.0 Cellular0/0/0 preference 80 # return