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I am experiencing an issue where Android Devices are consuming the DHCP Pool Range configured for my PXE boot. Is there a way to define Android Devices so they do not use the DHCP Range I have set for PXE. Here is the entry I have for my PXE DHCP Pool:

class "pxe" {
  match if ( substring ( option vendor-class-identifier, 0,9)="PXEClient") or
       ( substring ( option vendor-class-identifier, 0,5)="udhcp") ;
#  default-lease-time 60;
#  max-lease-time 60;
   default-lease-time 240;
   max-lease-time 240;
#  default-lease-time 7200;
#  max-lease-time 86400;

  # PXE bootp pool
  pool {
    allow members of "pxe";
    allow members of "sysrcd";
    filename "pxelinux.0";
  # Close PXE pool
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You only have a single (apparently too small) range for dhcp. You didn't specify how andoid devices are sucking up your addresses, so I'll assume wireless, b/c I've had the same problem. I will share with you a setup that seems to work well:

1)Have a separate DHCP scope for your wireless and LAN. This is possible on any decent router by assigning different address ranges on the different interfaces and/or VLANs, however you wish to separate your LAN and WLAN traffic. Which brings us to

2)Separate your Wireless and LAN traffic, you don't want fly-by-night android devices connecting to production workstations typically. If they're on the same subnet then they can reach your machines no question about it.


Okay, in the case for your laptops I would run 2 SSIDs, A Secure wireless for at least somewhat trusted devices or managed devices, and another for guests. Your secure wireless could be granted access to the LAN. That's 3 separate dhcp pools. Also, you could keep the lease time on your pxe pool very low, like 20-30 minutes, because once the imaging is finished the lease can be given away.

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The reason our Wireless network is on the same subnet is that we also have Laptops that connect to it in the conference rooms that need the ability to attach to and navigate the network. Is there any conceivable way to separate the Android Devices form using that pool? Also, the reason the PXE pool is so small, is we usually only have a few per day, and 10 would normally be more than enough for our needs, but since the Android devices are consuming them now, then that is causing a problem. Let me know your thoughts. – Brian Ingram Mar 27 '13 at 18:31
@BrianIngram I've updated. – BigHomie Mar 27 '13 at 21:02

If I were you I'd set a regular DHCP server serving all the devices and a proxyDHCP service providing the additional booting info only to PXE devices, then you do not have to use split pools.

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I'd really like to know the reason for the negative; so far it is just because of the downvoter ignorance. – Pat Jun 8 at 11:52

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