And I imagine that x.x.x.x can not be an address that refers to the DHCP server on the switch itself.
Is it true?
By definition it wouldn't need to be. If you have a L3 vlan interface on the switch and you create a DHCP pool for that vlan you wouldn't need an ip helper-address command. If you did need an ip helper-address command then the DHCP pool would not be on the switch.
as noted by Jon you don't need the ip helper address for locally defined DHCP pools.
In any case the broadcast DHCP request from client is process switched by the multilayer switch:
for locally defined pools the locally running DHCP server is used to pick up an address if one is available in the pool;
for IP subnets/SVIs where you want to rely to an external server the not routable DHCP request (S=0.0.0.0, D=255.255.255.255) is modified by the multilayer switch so that:
S=SVI ip address associated to broadcast domain that received the offer or that of interface towards the server ( more likely this )
D= unicast IP address of external server
inside the packet the GW address field is populated with the SVI ip address associated to broadcast domain that received the offer so that the the DHCP server can identify the DHCP pool to be used to pick up an address if one is available.
a sort of sequence number is added also to identify the transaction ( my guess)
the resulting packet can be routed to the external DHCP server.
Question We run asr9001 with XR 6.1.3, and we have a very long delay to
login w/ SSH 1 or 2 to the device compare to IOS device. After
investigation, the there is 1s delay between the client KEXDH_INIT and
the server (XR) KEXDH_REPLY. After debug ssh serv...
Introduction The purpose of this document is to demonstrate the Open
Shortest Path First (OSPF) behavior when the V-bit (Virtual-link bit) is
present in a non-backbone area. The V-bit is signaled in Type-1 LSA only
if the router is the endpoint of one or ...
Hi, I am seeing quite a few issues with patch install and wanted to
share my experience and workaround to this. Login to admin via CLI, then
access root with the “shell” command Issue “df –h” and you’ll probably
see the following directory full or nearly ...