Architecture : 3 x 3560 switches, ipservicesk9 image, linked by fibre trunks running EIGRP ...
Normal DHCP works - 4 VLANS, 1 uses fixed IP - the Server VLAN, 4 use DHCP.
Normal DHCP from VLans 3 to 5 works, I've configured in two ways, in both cases I can get DHCP to work correctly.
- DHCP in IOS with DNS on MS Server (2008 R2)
- DHCP and DNS on MS Server (2008 R2)
DNS server is 10.10.2.253, PXE Server is 10.10.2.251, these are my helper-address's ....
So all VLAN's can get an IP address from a server in the same VLAN as the PXE boot server - BUT - try PXE booting anything and it fails - the switches will not pass / forward the PXE boot 'DHCP discover' packets no matter what. I know the problems in the routing side of the switch, a packet trace proves it, I've done a packet trace in a flat network (the server VLAN) in which PXE boot works fine (so I know for sure my PXE server is OK), trying from another VLAN on the SAME switch (done as a test to eliminate the trunks) and all the initial PXE device 'DHCP discover' fails - the 'DHCP Discover' packets initiated under PXE boot are not routed or forwarded, they can be seen on the non server VLAN but they never appear in the server VLAN, hence not received and so the PXE boot process never starts.
I know I've asked this before but it went nowhere, why the hell would normal DHCP work and PXE boot not ?????????
It's getting frustrating - seriously so, I'm getting to the point where something is going to get launched ...
Being able to learn something is not the same thing as being able to do it for real. The only thing that exams prove is your memory.
