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Can you have multiple IP helpers?
Configuring an IP helper address You can configure up to 16 helper addresses on each interface. You can configure a helper address on an Ethernet port or a virtual interface.
What does a IP Helper do?
Internet Protocol Helper (IP Helper) assists network administration of the local computer by enabling applications to retrieve information about the network configuration of the local computer, and to modify that configuration.
Do Layer 3 switches have IP addresses?
Layer 3 switches have separate IP addresses on individual interfaces. Some devices have a factory default, such as 10.157. 22.154, used for troubleshooting during installation.
Why is DHCP relay needed?
A DHCP relay agent is any host that forwards DHCP packets between clients and servers. Relay agents are used to forward requests and replies between clients and servers when they are not on the same physical subnet.
How to enable IP Helper on access switches?
If you want to enable ip-helper on your access switches, then you need to assign ip to the vlan on access switches something like from 192.168.1.2 to 192.168.1.6. In this case all 6 switches will translate broadcast DHCP discover to unicast and send to DHCP server. DHCP server will receive 6 Discover and reply with 6 Offer.
Is it possible to have multiple IP Helper addresses?
If you have multiple IP helper addresses, a DHCP discover message is sent to all DHCP servers. The DHCP discovery process can then work out what server assigned the IP.. there are a lot of acknowledges and offers happening in the background that sorts this out. 08-10-2011 05:58 AM 08-10-2011 05:58 AM Yes, its possible.
Can a layer 2 switch use IP Helper?
If you want to set IP helper configuration on layer-2 switches, that switch needs to have an SVI IP address on that VLAN. Layer 2 switch will still use the core layer-3 switch to send the request to the DHCP server. The only thing layer-2 switch will do is to convert the broadcast request to unicast.
How to configure iphelper to relay DHCP with?
Because DHCP relay is a layer 3 feature, you configure it on an interface of a router. Basically the answer to your question is that you will have to configure a DHCP relay/IP helper on the router that “terminates” the layer 3 network on which you’d like to use DHCP.