how define network with mask 8 for dhcp server?

[Andreas Nilsson]

On Tue, Aug 6, 2013 at 10:59 AM, Andreas Nilsson <andrnils at gmail.com> wrote:

>
>
>
> On Tue, Aug 6, 2013 at 10:40 AM, Olivier Nicole <
> olivier.nicole at cs.ait.ac.th> wrote:
>
>> Sam,
>>
>> > my problem is to know how define a network with mask 8 and dhcp server
>> > works correctly with it! you know if i config my dhcpd.conf like below,
>> i
>> > have core dump either:
>> > subnet 10.0.0.0 netmask 255.0.0.0
>> > {
>> >     range 10.0.0.1 10.255.255.254;
>> > }
>> >
>> > do you know how should i define my range ??
>>
>> The reason may be that 2^24 machines in a subnet is such a non-sense
>> that dhcp simply cannot manage it.
>>
>> Best regards,
>>
>> Olivier
>>
>> >
>> > On Tue, Aug 6, 2013 at 12:23 PM, Olivier Nicole <
>> Olivier.Nicole at cs.ait.ac.th
>> >> wrote:
>> >
>> >> Sam,
>> >>
>> >> > subnet 192.0.0.0 netmask 255.0.0.0
>> >>
>> >> I know it is not the answer to your question, but you are wrong in your
>> >> guess that 192.0.0.0/8 is all private IPs. Only 192.168.0.0/16 is.
>> >>
>> >> I know that for certain because my own IP starts with 192.
>> >>
>> >> If you want a full /8 private, you can only use 10.0.0.0/8
>> >>
>> >> Bets regards,
>> >>
>> >> Olivier
>> >>
>> >> --
>> >>
>>
>>
> Well, I would guess it may run out of memory... I did a few tests:
> 192.0.0.0 - 192.128.255.255 does work ( using ~2.5Gb  RAM ).
> 192.0.0.0 - 192.192.255.255 does work ( using ~4Gb RAM ).
> 192.0.0.0 - 192.200.255.255 does work ( using ~4.2Gb RAM ).
> 192.0.0.0 - 192.224.255.255 dumps core
>
> Why would you want to have such a huge range?
>
> Best regards
> Andreas
>

Also, a quick look at the core file gives same indications:
#0  0x0000000800c67a21 in _malloc_prefork () from /lib/libc.so.7
#1  0x0000000800c6b72a in malloc () from /lib/libc.so.7
#2  0x000000000047b43b in omapi_object_dereference ()
#3  0x00000000004844db in do_ip4_hash ()
#4  0x0000000000484571 in do_ip4_hash ()
#5  0x0000000000438a45 in pool_timer ()
#6  0x000000000041dcd7 in trace_conf_stop ()
#7  0x000000000041fc4e in trace_conf_stop ()
#8  0x0000000000420698 in trace_conf_stop ()
#9  0x0000000000420ecc in trace_conf_stop ()
#10 0x0000000000420197 in trace_conf_stop ()
#11 0x00000000004247f3 in trace_conf_stop ()
#12 0x000000000041f210 in trace_conf_stop ()
#13 0x000000000040f3bf in lease_pinged ()
#14 0x000000000040d451 in ?? ()
#15 0x00000008007d7000 in ?? ()
#16 0x0000000000000000 in ?? ()

Best regards
Andreas