DHCP Server not sending offers!

[Glenn Satchell]

Hi Eugene

You are correct. The dynamic range is not used for hosts assigned an
address via a fixed-address statement. But different people are offering
ideas for you.

The "range dynamic-bootp" assigns bootp leases to clients. The difference
between bootp and dhcp is defined in several RFCs, but for our purpose we
can think of dhcp as an enhanced bootp. One of the noticeable differences
is that a bootp lease does not expire, so it is easy to run out of IPs if
you have too many clients, even over a long timne. Eg the PC you got rid
of two years ago is still holding one of your IPs. The isc-dhcp server
handles both types of leases in the same way, with a flag to distinguish
bootp from dhcp. It uses the same leases file. "range dynamic-bootp" was
an example in the example dhcpd.conf distributed by RedHat, so that's
probably where it came from.

I see that you are running dhcpd version 3.0.5. this is a very old
version, released in 2006. This was the default version with RedHat 5. If
you upgrade to RedHat 6.x you get version 4.1_something. There have been
many versions and fixes in the last 8 years. The next step before looking
at problems with your setup would be to upgrade to a current version and
see if you still see the problem. This is probably going to be the easiest
path. Your current dhcpd.conf looks like it would work without change.

This is from the Release Notes (RELNOTES) in a newer version:

                        Changes since 3.0.5

- Assorted fixes for broken network devices:  Packet length is now
  determined from the IP header length field to finally calculate the
  UDP payload length, because some NIC drivers return more data than
  they actually received.

regards,
-glenn

On Sat, July 19, 2014 12:07 am, Eugène Ngontang wrote:
> But Maarten, the dynamic range is for host whose ip address is not
> reserved. So if there nerver is a host requesting for a dynamic address,
> will there be a dynamic lease too? where do bootp store its leases? Is it
> in the same dhcpd.leases file?
>
> Thanks.
>
>
> 2014-07-18 15:48 GMT+02:00 Eugène Ngontang <sympavali at gmail.com>:
>
>> Ok Maarten, I will look at this.
>>
>> In fact I'm not the one who set the "range dynamic-bootp" clausure, I
>> guess the clients are using dhcp and bootp is not really required.
>>
>> But please, I know bootp is an old protocol, but I din't know the impact
>> of using this clausure. I would like if possible to have a link where
>> the
>> difference between the two clausures is explained, and the impact of
>> using
>> "range dynamic-bootp" in lease offers.
>>
>> I will try investigating this way. Thanks.
>>
>> Regards,
>> Eugène NG
>>
>>
>> 2014-07-18 14:36 GMT+02:00 Maarten Carels <lists at carels.info>:
>>
>>> On 18 Jul 2014, at 14:22 , Eugène Ngontang <sympavali at gmail.com>
>>> wrote:
>>>
>>> > @Maarten, that is what I didn't figure out.
>>> >
>>> > Nevertheless, I have a dynamic range, and fixed addresses.
>>> >
>>> > Please explain in more detail what you mean in your post about bootp.
>>> Thank you my dear.
>>>
>>> If all your clients are using dhcp, change the range statement to
>>>     range 1.1.1.50 1.1.1.100;
>>>
>>> bootp is an old protocol that lacks the automatic lease expiration.
>>>
>>> And look at the place where the server is logging, usually somewhere in
>>> /var/log. If it thinks it can't give a lease, it will log why.
>>>
>>> --maarten
>>>
>>> _______________________________________________
>>> dhcp-users mailing list
>>> dhcp-users at lists.isc.org
>>> https://lists.isc.org/mailman/listinfo/dhcp-users
>>>
>>
>>
>>
>> --
>> ngonta_e at epitech.net
>> sympavali at gmail.com
>> ------------------------------------------------------------
>> *Aux hommes il faut un chef, et au*
>>
>> * chef il faut des hommes! L'habit ne fait pas le moine, mais lorsqu'on
>> te
>> voit on te juge!*
>>
>
>
>
> --
> ngonta_e at epitech.net
> sympavali at gmail.com
> ------------------------------------------------------------
> *Aux hommes il faut un chef, et au*
>
> * chef il faut des hommes!L'habit ne fait pas le moine, mais lorsqu'on te
> voit on te juge!*
> _______________________________________________
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