Well, this has been interesting... I read the original posters' question as being one thing, and responded accordingly. Everyone else responded to the question, looking at it from a different angle than I was.
Jose, can you clarify if these two DHCP Servers are acting as backups or load balance for each other, i.e., they are configured for the same Subnet in scope definition, but are dividing the scope (subnet) in half (one half of the subnet on one DHCP Server, the other half on the other server)?? Or... are the DHCP Servers serving up multiple subnets, with the Router only having one Ethernet interface to route between the subnets... and the DHCP Servers are both running on the Ethernet side of the network?? Are any of the DHCP hosts on the WAN side of the Router?? Just looking for clarity to make sure I'm not reading the question wrong. -----Original Message----- From: Tribavan Raina [mailto:[EMAIL PROTECTED]] Sent: Thursday, August 29, 2002 4:18 PM To: [EMAIL PROTECTED] Subject: RE: Multiple Helper-addresses on same interface [7:52305] I have seen it like this f I have two ip helper-address statements on the Ethernet interface of the router, each one pointing to a different DHCP server, will the router send the unicast message to each server? Yes the router will send request to both the servers and will forward the reply from both the servers to the client.It depends upon client what address it chooses. Tribavan Raina -----Original Message----- From: Mark W. Odette II [mailto:[EMAIL PROTECTED]] Sent: Friday, August 30, 2002 6:54 AM To: [EMAIL PROTECTED] Subject: RE: Multiple Helper-addresses on same interface [7:52305] IIRC, the way you make this work is to make the Ethernet interface(on the Router) a trunk link to your switch with ISL or dot1q Vlans. Each VLan represents the Subnet of choice. With this in place, you enable routing between the vlans on the router, and then configure the IP Helper address on the main interface of the Ethernet (this part I may be recanting incorrectly) port. The router will then forward DHCP requests to the appropriate DHCP server based upon what interface the request came from. I don't believe the multiple IP Helper addresses config will work with an Ethernet interface configured with a secondary address. If I've stated in error the proper configuration process, someone will correct me shortly. If I AM in error, it's only because I've never had to do it before... but have read the topic a couple of times on this mail list. Good Luck! Mark -----Original Message----- From: Quezada, Jose L [mailto:[EMAIL PROTECTED]] Sent: Thursday, August 29, 2002 1:04 PM To: [EMAIL PROTECTED] Subject: Multiple Helper-addresses on same interface [7:52305] Hello all, Can anyone enlighten me on the behavior of having multiple "ip helper-address" statements on the same interface? We are setting up a DHCP solution where we will have two DHCP servers and the Cisco router serving as the relay agent. If I have two ip helper-address statements on the Ethernet interface of the router, each one pointing to a different DHCP server, will the router send the unicast message to each server?? Or will it randomly send it to one or the other? Or if one server is not available, the router will send the unicast message to the server that is available? What does the router do with multiple ip helper-address statements? Any help would be appreciated. Thanks. Joe Quezada Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=52325&t=52305 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
