How to reinitiate DHCP Discover if response to GW is not available on Cisco Router as DHCP Client (IPoE)

[FahadAliKhan36275]

Hi All

I am using Cisco CPE (current testing on EVE using vIOS) as IPoE (DHCP Client) to get IP address from BNG in the network. There are Two BNGs in the network (Stateless). In case of Failure to BNG1 request re-routed to BNG2. The lease-time is around 24 hours (and cannot be reduce as per requirement), with Renew and Rebind timers are also high. When Network failure happen DHCP Request/Renew goes to BNG2 and it reject the request as it don't have any state of that CPE. So CPE has to wait for some time before clear the lease and start DHCP Discovery again. During this whole time even though the 2nd path and BNG is available but no service to CPE.

I wish to know if there is any way (like using IP SLA) to track the gateway IP. and after failure of certain replies, CPE lease clear and it can initiate new DHCP Discover which will be entertain by BNG2.

Regards

Fahad

[FahadAliKhan36275]

I have findout the way...but if there is any more appropriate solution available, than will like to know.

I have tracked the gateway IP using IP SLA and using event manager, shut & unshut the interface (where DHCP client is configured).

ip sla 10
icmp-echo 101.116.0.1
frequency 5
ip sla schedule 10 life forever start-time now
!

track 10 ip sla 10
delay down 5 up 10

!

event manager applet DHCPReset
event track 10 state down
action 1 cli command "enable"
action 2 cli command "conf t"
action 3 cli command "interface gig0/0"
action 4 cli command "shut"
action 5 cli command "no shut"
action 6 cli command "end"
!

*Jul 13 04:22:24.977: %TRACK-6-STATE: 10 ip sla 10 state Up -> Down
*Jul 13 04:22:30.817: %SYS-5-CONFIG_I: Configured from console by on vty0 (EEM:DHCPReset)
*Jul 13 04:22:42.314: %DHCP-6-ADDRESS_ASSIGN: Interface GigabitEthernet0/0.400 assigned DHCP address 101.116.0.26, mask 255.255.240.0, hostname CPE1

CPE1#
CPE1#
CPE1#
CPE1#
CPE1#
*Jul 13 04:23:04.977: %TRACK-6-STATE: 10 ip sla 10 state Down -> Up

/Fahad