Need for Cisco router internet backup

[leowang0801]

Now, I have Cisco router 2811 connected with DSL to internet, which I have web sites host to let people login to my web base application. For redundant, I need to setup two modems connected with cisco router to let people dial in and can login my application like normal way. Is it possible to do that?
Thanks.

 

[COMPUTERTECH33]

interface Ethernet0
backup delay 10 60
backup interface Async5
ip address xxxxxxxxxxxx 255.255.255.248
ip nat outside
no ip route-cache
no ip mroute-cache
half-duplex
crypto map nolan
!
interface FastEthernet0
ip address 192.168.17.1 255.255.255.0
ip helper-address 172.17.2.30
ip helper-address 172.17.2.255
ip helper-address 172.17.255.255
ip helper-address 172.16.255.255
ip directed-broadcast
ip nat inside
no ip route-cache
no ip mroute-cache
speed auto
!
interface Async5
ip address 170.1.1.16 255.255.0.0
encapsulation ppp
keepalive 10
dialer in-band
dialer idle-timeout 300
dialer string xxxxxxxxxxx
dialer-group 1
fair-queue 64 16 0
ppp authentication chap
!
interface Dialer1
no ip address
no cdp enable
!
ip nat inside source route-map nonat interface Async5 overload
ip kerberos source-interface any
ip classless
no ip forward-protocol udp netbios-ns
no ip forward-protocol udp netbios-dgm
ip forward-protocol udp netbios-ss
ip forward-protocol udp 42508
ip route 0.0.0.0 0.0.0.0 xxxxxxxx...Ip of E0
ip route 0.0.0.0 0.0.0.0 Async5 200
no ip http server
!
no logging trap
logging facility local0
logging 172.17.1.31
access-list 3 permit any
access-list 110 deny ip 192.168.17.0 0.0.0.255 172.16.0.0 0.0.255.255
access-list 110 deny ip 192.168.17.0 0.0.0.255 172.17.0.0 0.0.255.255
access-list 110 permit ip 192.168.17.0 0.0.0.255 any
access-list 120 permit ip 192.168.17.0 0.0.0.255 172.16.0.0 0.0.255.255
access-list 120 permit ip 192.168.17.0 0.0.0.255 172.17.0.0 0.0.255.255
access-list 121 permit ip 192.168.17.0 0.0.0.255 172.16.0.0 0.0.255.255
access-list 121 permit ip 192.168.17.0 0.0.0.255 172.17.0.0 0.0.255.255
access-list 150 permit esp host xxxxxxx host 0.0.0.0
access-list 150 permit udp host xxxxxxx host 0.0.0.0 eq isakmp
access-list 150 permit ip any 192.168.16.0 0.0.0.255
access-list 150 permit ip any 192.168.17.0 0.0.0.255
priority-list 1 protocol ip high
dialer-list 1 protocol ip permit
route-map nonat permit 10
match ip address 110
!
snmp-server engineID local xxxxxxxxxxxxxx
snmp-server community xxxx RO
banner motd ^CCC
xxxxxxxxxxx
Unauthorized access is prohibited
Violators will be prosecuted
xxxxxxxxxx
^C
!
line con 0
password 7 xxxxxxx
login
transport input none
line aux 0
password 7 xxxxxxxxxxxx
autoselect ppp
modem InOut
modem autoconfigure discovery
transport input all
autohangup
speed 115200
flowcontrol hardware
line vty 0 4
access-class 3 in
password 7 xxxxxxxxxxx
login
!