[ipxe-devel] iPXE with specific list of DHCP server(s)

[James A. Peltier]

----- Original Message -----
| ----- Original Message -----
| | 
| | --------------------------------------------
| | On Mon, 10/14/13, Michael Brown <mbrown at fensystems.co.uk> wrote:
| | 
| |  On 14/10/13 08:13, Shantanu Gadgil
| |  wrote:
| |  > I was wondering if I can *specify* the the DHCP
| |  server(s) that I want iPXE to accept OFFERs from (using IP
| |  address) and ignore others.
| |  > The situation is that there could be more than one DHCP
| |  server.
| |  
| |  There is no support for doing this in iPXE.  Such a
| |  requirement would normally indicate that the network is
| |  misconfigured; what is the motivation for wanting this
| |  functionality?
| | 
| | 'Misconfiguration' ... I don't think so! :)
| | /If the dhclient protocol/config/whatever has a 'reject' setting,
| | why
| | can't it have a
| | an 'accept_only' setting?/
| | 
| | That said, let me explain the real situation ...
| | 
| | The IT guys already have one DHCP server running per subnet. (for
| | network booting)
| | 
| | I want to deploy my own PXE booting network, parallel to theirs to
| | try out iPXE.
| | (which would point the PXE clients to *my* installation server,
| | rather than theirs.
| | 
| | Having this feature allows me to test an alternate configuration
| | even
| | when the machine's
| | MAC address is present in the IT network.
| | 
| | Regards,
| | Shantanu
| 
| Which is exactly a network misconfiguration.  You're attempting to
| circumvent your IT Services infrastructure in favour of your own.
|  If you want a test bed, set on up.  You don't need a "real" network
| to test iPXE.
| 
| --
| James A. Peltier
| Manager, IT Services - Research Computing Group
| Simon Fraser University - Burnaby Campus
| Phone   : 778-782-6573
| Fax     : 778-782-3045
| E-Mail  : jpeltier at sfu.ca
| Website : http://www.sfu.ca/itservices
| 
| “A successful person is one who can lay a solid foundation from the
| bricks others have thrown at them.” -David Brinkley via Luke Shaw

I should mention the following.  If you have a DHCP server that is local to the network and it answers faster than the IT Services DHCP server your requests *MAY* be answered by it first.  However, you should only use such a configuration with the deny unknown-clients DHCP option so that your server doesn't answer requests for any other hosts other than your test hosts.

Keep in mind that this is a big if your server answers first.  You may end up getting a request from yours then a request from theirs than a request from theirs then a request from yours, not having ANY clue other than the server IP that's answering the request to know if your "testing" is working.

To me, fundamentally your testing methodology is broken.

-- 
James A. Peltier
Manager, IT Services - Research Computing Group
Simon Fraser University - Burnaby Campus
Phone   : 778-782-6573
Fax     : 778-782-3045
E-Mail  : jpeltier at sfu.ca
Website : http://www.sfu.ca/itservices

“A successful person is one who can lay a solid foundation from the bricks others have thrown at them.” -David Brinkley via Luke Shaw