i created a new vlan and added a ip helper-address command. the ip in the helper-address will be my primary dhcp server, but i have my secondary dhcp server how do i add this in the configuration give another ip helper-address to the vlan and how do i mention that one is primary and another is secondary
ip address 172.25.5.1 255.255.255.0
ip helper-address 172.25.1.5
the idea is one dhcp server goes down it has to go to the other dhcp server
please let me know you suggestions
Just to expand on John's answer. You don't have a primary and secondary, they are both used. So you need to make sure that each DHCP server is not handing out the same addresses eg.
192.168.5.0/24 subnet. You would split this between the 2 DHCP servers by splitting it in half eg.
192.168.5.0/25 on DHCP server 1
192.168.5.128/25 on DHCP server 2
Whichever DHCP responds first is generally the one used which is not an issue if you split the scopes correctly.
You just add another line. You can't define primary or secondary. It's just going to take whichever responds first.