Is this supposed to happen?

[Glenn Satchell]

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>Date: Wed, 15 Nov 2006 07:05:32 -0600
>From: Steven <zamdrist at gmail.com>
>To: dhcp-users at isc.org
>Subject: Re: Is this supposed to happen?
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>On 11/15/06, Simon Hobson <dhcp1 at thehobsons.co.uk> wrote:
>>
>> Steven wrote:
>>
>> >Running ZenWalk 2.8 here. Installed and configured dhclient with no
>> >problems, I can run it and connect to the Internet. I'm hooked up
>> directely
>> >to a cable modem, Comcast.
>> >After some arbitrary period of time I lose my connection however, appears
>> to
>> >have something to do with lease renewal? If so how can I run dhclient and
>> >stay connected? Any help would be greatly appreciated. Thank you.
>>
>> We might be able to help if we had something to go on !
>>
>> Is the time before losing your connection arbitrary (and random) or a
>> fixed period ?
>>
>> Does this period relate to the lease time your client has been given ?
>>
>> Is anything logged (by dhclient or anything else) when you lose your
>> connection ?
>>
>> Does re-running dhclient get you reconnected ? Do you get the same address
>> ?
>>
>>
>syslog:
>
>Nov 14 09:25:00 laptop dhclient: receive_packet failed on eth0: Network is
>downNov 14 09:43:31 laptop dhclient: send_packet: Network is unreachable
>Nov 14 09:43:31 laptop dhclient: send_packet: please consult README file
>regarding broadcast address.
>
>I'm able to do: dhclient -r, and then dhclient to get reconnected no
>problem. According to dhcp.leases I'm getting the same ip address when I
>reconnect.
>
>The period of time seems to be random, not set time periods.
>
>Thanks!

Do you have firewall rules blocking some of the dhcp traffic? Anything
about iptables(?) in syslog?

Initially the client gets an address via broadcast then does unicast to
renew it. Perhaps the unicast responses to the dhcp server is being
blocked?

If you re-run dhclient with no switches, only the interface name does
it correctly update the lease times? If not this might indicate a
problem getting the unicast packets back to the dhcp server.

regards,
-glenn