How does a DHCP relay router forward the packet to the server?Linux DHCP-Helper: GIADDR is not the source IP addressHow broadcasting works on different networks?How DHCP OFFER unicast works?Cisco Small-business switch - DHCP Relay offer packet droppedCan/Should a DHCP server send a DHCPDISCOVER message?How DHCP works?How does a router relay DHCP packets when it is configured as a relay agent?DHCP relay bindingAssign DHCP IP address on Cisco router interfaceDHCP relay on Juniper MX
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How does a DHCP relay router forward the packet to the server?
Linux DHCP-Helper: GIADDR is not the source IP addressHow broadcasting works on different networks?How DHCP OFFER unicast works?Cisco Small-business switch - DHCP Relay offer packet droppedCan/Should a DHCP server send a DHCPDISCOVER message?How DHCP works?How does a router relay DHCP packets when it is configured as a relay agent?DHCP relay bindingAssign DHCP IP address on Cisco router interfaceDHCP relay on Juniper MX
We know that routers do not forward broadcast messages. So when a DHCP relay router receives a DHCP Discover message, the destination IP address is going to be 255.255.255.255 because at this stage the client does not know the DHCP Server's IP address. So why does the router not drop the packet? How does it forward the packet to the server? Since my understanding is that the router will see layer 3 and drop it since it saw a broadcast address.
dhcp
asked 6 hours ago
iiTechiiiiTechii
374
add a comment |
We know that routers do not forward broadcast messages. So when a DHCP relay router receives a DHCP Discover message, the destination IP address is going to be 255.255.255.255 because at this stage the client does not know the DHCP Server's IP address. So why does the router not drop the packet? How does it forward the packet to the server? Since my understanding is that the router will see layer 3 and drop it since it saw a broadcast address.
dhcp
asked 6 hours ago
iiTechiiiiTechii
374
add a comment |
We know that routers do not forward broadcast messages. So when a DHCP relay router receives a DHCP Discover message, the destination IP address is going to be 255.255.255.255 because at this stage the client does not know the DHCP Server's IP address. So why does the router not drop the packet? How does it forward the packet to the server? Since my understanding is that the router will see layer 3 and drop it since it saw a broadcast address.
dhcp
asked 6 hours ago
iiTechiiiiTechii
374
We know that routers do not forward broadcast messages. So when a DHCP relay router receives a DHCP Discover message, the destination IP address is going to be 255.255.255.255 because at this stage the client does not know the DHCP Server's IP address. So why does the router not drop the packet? How does it forward the packet to the server? Since my understanding is that the router will see layer 3 and drop it since it saw a broadcast address.
dhcp
dhcp
asked 6 hours ago
iiTechiiiiTechii
374
asked 6 hours ago
iiTechiiiiTechii
374
asked 6 hours ago
iiTechiiiiTechii
374
asked 6 hours ago
iiTechiiiiTechii
374
asked 6 hours ago
iiTechiiiiTechii
374
374
add a comment |
add a comment |
2 Answers
2
active
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The DHCP relay agent (router, or otherwise) creates a unicast DHCP request for the DHCP server(s) configured in the relay agent. The DHCP server replies to the relay agent, which then sends the response back to the requester.
You can see all the details of how this works in RFC 2131, Dynamic Host Configuration Protocol, which explains that DHCP relay inherits the BOOTP relay.
answered 6 hours ago
Ron Maupin♦Ron Maupin
69k1370126
add a comment |
DHCP relay is not a routing function, even if it is usually activated on a router, but it's also used on switches (L2 and L3). You should see the relay agent as a network service like the DHCP server itself. In fact, it's more like a proxy than a routing function.
DHCP relay can't just forward the bare discovery, but needs to change several DHCP fields to enable proper handling by the DCHP server. Most often option 82 is also inserted to provide further information about the relay agent (vendor-id and remote-id) and the interface the client is located on (circuit-id).
answered 30 mins ago
Zac67Zac67
33.6k22167
add a comment |
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2 Answers
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2 Answers
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The DHCP relay agent (router, or otherwise) creates a unicast DHCP request for the DHCP server(s) configured in the relay agent. The DHCP server replies to the relay agent, which then sends the response back to the requester.
You can see all the details of how this works in RFC 2131, Dynamic Host Configuration Protocol, which explains that DHCP relay inherits the BOOTP relay.
answered 6 hours ago
Ron Maupin♦Ron Maupin
69k1370126
add a comment |
The DHCP relay agent (router, or otherwise) creates a unicast DHCP request for the DHCP server(s) configured in the relay agent. The DHCP server replies to the relay agent, which then sends the response back to the requester.
You can see all the details of how this works in RFC 2131, Dynamic Host Configuration Protocol, which explains that DHCP relay inherits the BOOTP relay.
answered 6 hours ago
Ron Maupin♦Ron Maupin
69k1370126
add a comment |
The DHCP relay agent (router, or otherwise) creates a unicast DHCP request for the DHCP server(s) configured in the relay agent. The DHCP server replies to the relay agent, which then sends the response back to the requester.
You can see all the details of how this works in RFC 2131, Dynamic Host Configuration Protocol, which explains that DHCP relay inherits the BOOTP relay.
answered 6 hours ago
Ron Maupin♦Ron Maupin
69k1370126
The DHCP relay agent (router, or otherwise) creates a unicast DHCP request for the DHCP server(s) configured in the relay agent. The DHCP server replies to the relay agent, which then sends the response back to the requester.
You can see all the details of how this works in RFC 2131, Dynamic Host Configuration Protocol, which explains that DHCP relay inherits the BOOTP relay.
answered 6 hours ago
Ron Maupin♦Ron Maupin
69k1370126
answered 6 hours ago
Ron Maupin♦Ron Maupin
69k1370126
answered 6 hours ago
Ron Maupin♦Ron Maupin
69k1370126
answered 6 hours ago
Ron Maupin♦Ron Maupin
69k1370126
69k1370126
add a comment |
add a comment |
DHCP relay is not a routing function, even if it is usually activated on a router, but it's also used on switches (L2 and L3). You should see the relay agent as a network service like the DHCP server itself. In fact, it's more like a proxy than a routing function.
DHCP relay can't just forward the bare discovery, but needs to change several DHCP fields to enable proper handling by the DCHP server. Most often option 82 is also inserted to provide further information about the relay agent (vendor-id and remote-id) and the interface the client is located on (circuit-id).
answered 30 mins ago
Zac67Zac67
33.6k22167
add a comment |
DHCP relay is not a routing function, even if it is usually activated on a router, but it's also used on switches (L2 and L3). You should see the relay agent as a network service like the DHCP server itself. In fact, it's more like a proxy than a routing function.
DHCP relay can't just forward the bare discovery, but needs to change several DHCP fields to enable proper handling by the DCHP server. Most often option 82 is also inserted to provide further information about the relay agent (vendor-id and remote-id) and the interface the client is located on (circuit-id).
answered 30 mins ago
Zac67Zac67
33.6k22167
add a comment |
DHCP relay is not a routing function, even if it is usually activated on a router, but it's also used on switches (L2 and L3). You should see the relay agent as a network service like the DHCP server itself. In fact, it's more like a proxy than a routing function.
DHCP relay can't just forward the bare discovery, but needs to change several DHCP fields to enable proper handling by the DCHP server. Most often option 82 is also inserted to provide further information about the relay agent (vendor-id and remote-id) and the interface the client is located on (circuit-id).
answered 30 mins ago
Zac67Zac67
33.6k22167
DHCP relay is not a routing function, even if it is usually activated on a router, but it's also used on switches (L2 and L3). You should see the relay agent as a network service like the DHCP server itself. In fact, it's more like a proxy than a routing function.
DHCP relay can't just forward the bare discovery, but needs to change several DHCP fields to enable proper handling by the DCHP server. Most often option 82 is also inserted to provide further information about the relay agent (vendor-id and remote-id) and the interface the client is located on (circuit-id).
answered 30 mins ago
Zac67Zac67
33.6k22167
answered 30 mins ago
Zac67Zac67
33.6k22167
answered 30 mins ago
Zac67Zac67
33.6k22167
answered 30 mins ago
Zac67Zac67
33.6k22167
33.6k22167
add a comment |
add a comment |
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