dhcp_relay with multiple DHCP Servers 1

[JasReehal]

Hi Everyone,

For resilience I have 2 DHCP servers in the 192.168.100.0 vlan, serving without overlapping addresses. If one DHCP server goes down the other one can respond.

I use dhcp_relay in VLAN without it's own DHCP server. How can a client in the other vlans access both servers. Do I have two dhcp_relay commands? is this possible?

 

[biv343]

You can have multiple DHCP servers/relay hosts for a single vlan.

 

[JasReehal]

Thanks to biv343, I now know I have to issue the dhcp_relay command twice for my two DHCP servers. BUT ...

Just to make it 'crystal clear'; consider the scenario
[ul]
[li]I have 2 DHCP Servers in my default VLAN, addresses 192.168.1.7 and 192.168.1.8[/li]
[li]I have another vlan 192.168.100.0/24 which has NO DHCP servers.[/li]
[/ul]

The general form of the 'ip dhcp_relay' command is...

ip dhcp_relay fwd-path <ADDR1> <ADDR2> enable

for instance...

ip dhcp_relay fwd-path 192.168.100.254 192.168.1.7 enable
ip dhcp_relay fwd-path 192.168.100.254 192.168.1.8 enable


In my case I will use this command twice for my two DHCP servers
where <ADDR2> will be 192.168.1.7 and 192.168.1.8.

What address do I use for <ADDR1>? do I use 192.168.100.254 in BOTH of
my dhcp_relay commands? Do I use another address? If so what?

What does <ADDR1> signify in the general dhcp_relay command?

Is it an an arbitrary address for a 'virtual' DHCP server in the vlan?
Is it the address or the vlan router interface?
Can anyone tell me?

 

[Yaoul]

Hi,

<ADDR1> is the IP address of your Nortel device in the users VLAN.

Cheers,

y/