IP/MPLS Cloud DHCP Relay

[adrianalcalde]

Hello all:
I am having issues relaying dhcp requests between vprn's in an IP/MPLS cloud. I'm not sure if I'm doing it correctly, I'm a bit new with ALU, thanks in advance for any suggestions.

The topology for the service:


Location 1 VPRN 321:
2 interfaces with address assigned, and RVPLS with spoke-sdp.
1) VPLS 319: "MGMT". IP: 172.100.0.1/24.
DHCP server configured behind it (172.100.0.254)

2) VPLS 322 : "Location1". IP: 172.16.0.1/24.
DHCP Clients.
This VPLS is extended to 7210 SAS devices with spoke-sdp and clients are connected to sap's on the 7210. DHCP works perfect here obtaining addresses from 172.100.0.25.

Location 2 VPRN 321:
1 interface with address assigned, and RVPLS with spoke-sdp.
1) VPLS 323: "Location2". IP: 172.16.1.1/24
DHCP Clients. This VPLS is extended to 7210 SAS devices with spoke-sdp and clients are connected to sap's on the 7210. DHCP broadcasts are not reaching DHCP server in Location 1.

Location 3 VPRN 321:
Same issue as Location 2 in Location 3, not going to copy, but I'm pretty sure whatever I use to fix Location 2 will be the same for Location 3.


If I assign a client a static IP address in Location 2 (let's say 172.16.1.5, I can route between the VPRN's without issue, and even ping 172.100.0.254.

I've tried multiple variations of using relay proxy and dhcp snoop but my broadcast from Client is replied to. ALU documentation primarily seems to talk about DHCP and DHCP relay for Triple Play services. I'm using Infoblox as a DHCP server, but I get the same results with local-dhcp-server.

LOCATION 1:
*A:LAB-7750-SR12-1# /configure service vprn 321
*A:LAB-7750-SR12-1>config>service>vprn# info
----------------------------------------------
router-id 192.168.1.1
autonomous-system 65001
route-distinguisher 65001:1
auto-bind-tunnel
resolution-filter
rsvp
exit
resolution filter
exit
vrf-target target:65001:0
interface "Local-Loopback-1" create
address 192.168.1.1/32
loopback
exit
interface "Location1_GW" create
address 172.16.0.1/24
dhcp
server 172.100.0.254
no shutdown
exit
ip-mtu 9000
vpls "Accedian L3 - Location 1"
exit
exit
interface "to_VPLS319_MGMT" create
address 172.100.0.1/24
allow-directed-broadcasts
dhcp
server 172.100.0.254
no shutdown
exit
ip-mtu 9000
vpls "Accedian L3 MGMT VPLS"
exit
exit
bgp
router-id 192.168.1.1
no shutdown
exit
service-name "Accedian L3 Discovery Test"
no shutdown
----------------------------------------------

*A:LAB-7750-SR12-1>config>service>vprn# /configure service vpls 319
*A:LAB-7750-SR12-1>config>service>vpls# info
----------------------------------------------
service-mtu 9014
allow-ip-int-bind
exit
stp
shutdown
exit
service-name "Accedian L3 MGMT VPLS"
sap 6/1/3:319 create
no shutdown
exit
no shutdown

*A:LAB-7750-SR12-1>config>service>vpls# info
----------------------------------------------
service-mtu 9014
allow-ip-int-bind
exit
stp
shutdown
exit
service-name "Accedian L3 - Location 1"
spoke-sdp 1648:322 create
no shutdown
exit
spoke-sdp 1649:322 create
no shutdown
exit
no shutdown
----------------------------------------------

LOCATION 2:

*A:LAB-MTS-SRc12-A>config>service>vprn# info
----------------------------------------------
router-id 192.168.2.1
autonomous-system 65001
route-distinguisher 65001:2
auto-bind-tunnel
resolution-filter
rsvp
exit
resolution filter
exit
vrf-target target:65001:0
interface "Local-Looopback-2" create
address 192.168.2.1/32
loopback
exit
interface "Location2_GW" create
address 172.16.1.1/24
allow-directed-broadcasts
dhcp
server 172.100.0.254
no shutdown
exit
ip-mtu 9000
vpls "Accedian L3 - Location 2"
exit
exit
bgp
router-id 192.168.2.1
no shutdown
exit
service-name "Accedian L3 Discovery Test"
no shutdown
----------------------------------------------

*A:LAB-MTS-SRc12-A>config>service>vpls# /configure service vpls 323
*A:LAB-MTS-SRc12-A>config>service>vpls# info
----------------------------------------------
service-mtu 9014
allow-ip-int-bind
exit
stp
shutdown
exit
service-name "Accedian L3 - Location 2"
spoke-sdp 11424:323 create
no shutdown
exit
no shutdown
----------------------------------------------

LOCATION 3:
A:LABMTSSRc12B# /configure service vprn 321
A:LABMTSSRc12B>config>service>vprn# info
----------------------------------------------
router-id 192.168.3.1
autonomous-system 65001
route-distinguisher 65001:3
auto-bind-tunnel
resolution-filter
rsvp
exit
resolution filter
exit
vrf-target target:65001:0
interface "Local-Loopback-3" create
address 192.168.3.1/32
loopback
exit
interface "Location3_GW" create
address 172.16.2.1/24
allow-directed-broadcasts
dhcp
server 172.100.0.254
no shutdown
exit
ip-mtu 9000
vpls "Accedian L3 - Location 3"
exit
exit
bgp
router-id 192.168.3.1
no shutdown
exit
service-name "Accedian L3 Discovery Test"
no shutdown
----------------------------------------------

A:LABMTSSRc12B>config>service>vpls# info
----------------------------------------------
service-mtu 9014
allow-ip-int-bind
exit
stp
shutdown
exit
service-name "Accedian L3 - Location 3"
spoke-sdp 1458:324 create
no shutdown
exit
no shutdown
----------------------------------------------

Let me know if I can provide any other information to help.

Thanks in advance!

[Sargremor]

Here is a sample of a config I use in a local VPRN. I can't see why it wouldn't be working, all is needed is that all PEs in the VPRN can reach the DHCP server.

dhcp
local-dhcp-server "SRV-DHCP" create
use-gi-address
pool "AP-CTR" create
max-lease-time min 10
subnet 10.72.0.0/20 create
options
exit
exclude-addresses 10.72.0.0 10.72.0.5
address-range 10.72.0.6 10.72.7.254
exit
exit
no shutdown
exit
exit
route-distinguisher 6758:30048810
interface "To-LAN" create
address 10.72.0.4/20
dhcp
server 172.26.0.10
trusted
gi-address 10.72.0.4
no shutdown
exit
vpls "VPLS-40"
exit
exit
interface "Local-DHCP-SRV" create
address 172.26.0.10/32
local-dhcp-server "SRV-DHCP"
loopback
exit

[adrianalcalde]

Thanks for the response. Local DHCP works within the same vprn (from host's on the rvpls that are on the same vprn and NE that the dhcp server is on), but what doesn't work is hosts trying to obtain dhcp address from hosts on the same vprn but differnet NE. The broadcasts are not reaching the dhcp server from packet captures I've ran. I think the issue is with proxy-arp, will update once I set this up and test.