topic Re: DHCP and VRF in Routing and SD-WAN

DHCP and VRF

vin.marco — Tue, 05 Dec 2023 13:52:37 GMT

I have a problem with C6800.

I configured the DHCP service but the vrf VRF-A command does not exist?

ip dhcp excluded-address 10.xx.xx.1 ip dhcp pool VoIP_UC14_V254 network 10.xx.xx.0 255.255.255.0 default-router 10.xx.xx.1 option 150 ip 10.xx.x.132 10.xx.x.132 dns-server 10.xx.xx.151 10.xx.xx.158 ! 6807_VSS(dhcp-config)#? DHCP pool configuration commands: address Configure a reserved address bootfile Boot file name client-identifier Client identifier client-name Client name default-router Default routers dns-server DNS servers domain-name Domain name exit Exit from DHCP pool configuration mode hardware-address Client hardware address host Client IP address and mask import Programatically importing DHCP option parameters lease Address lease time netbios-name-server NetBIOS (WINS) name servers netbios-node-type NetBIOS node type network Network number and mask next-server Next server in boot process no Negate a command or set its defaults option Raw DHCP options remember Remember released bindings renew Configure renewal policy reserved-only Only allocate reserved addresses 6807_VSS(dhcp-config)#vrf ? % Unrecognized command VSS(dhcp-config)#vrf

How is it possible ?

The 6800 has a 6T Supervisor Engine and IOS 15.5(1)SY6

Re: DHCP and VRF

M02@rt37 — Tue, 05 Dec 2023 17:18:49 GMT

Hello @vin.marco

ip dhcp using vrf is not supported on IOS versions for the 6500 or 6800 series.

Re: DHCP and VRF

vin.marco — Tue, 05 Dec 2023 17:33:26 GMT

So it's not possible to make DHCP work in VRF on the 6800?

Re: DHCP and VRF

MHM Cisco World — Tue, 05 Dec 2023 17:34:51 GMT

Hmm'

It dhcp pool vrf aware only work for router it so limited in SW.

Now we have issue

Let me try something in lab

Maybe it works.

If it work I will send you solution.

MHM

Re: DHCP and VRF

balaji.bandi — Tue, 05 Dec 2023 17:38:04 GMT

Not that we aware that was working on IOS 15.X code.

Re: DHCP and VRF

MHM Cisco World — Thu, 07 Dec 2023 09:40:46 GMT

Hi again'

I check my note

Are relay use

Ip dhcp relay option vpn-id

In global mode ?

If not then why you need vrf aware dhcp pool?

MHM

Re: DHCP and VRF

vin.marco — Mon, 11 Dec 2023 15:10:46 GMT

I wanted to update you, even without the vrf XXX command the server releases IP addresses.

I don't know why but it works

Re: DHCP and VRF

M02@rt37 — Mon, 11 Dec 2023 15:13:35 GMT

Thanks for your feedback @vin.marco

Re: DHCP and VRF

MHM Cisco World — Mon, 11 Dec 2023 15:19:30 GMT

We use vrf under dhcp only for mpls and we make dhcp relay push vpn id' here you dont need it you dont have mpls and the dhcp subnet is reachable via server (I think via leaking route).

So that why I ask do you use vpn-id dhcp relay.

It will work no problem.

MHM