Help with Linux and DHCP

[Jerry Feldman]

dhcpc has a logging option. When I was having trouble with dhclient on 
earlier versions of dhclient, I turned on logging. You also might want to 
check the contents of /var/state/dhcp. On my system:
gaf at lap:/var/state/dhcp > ls -l
total 8
-rw-------   1 root     root          124 Mar  1 09:39 dhcpcd-eth0.cache
-rw-r--r--   1 root     root          374 Mar  1 09:39 dhcpcd-eth0.info
The info file contains all the info regarding my current connection.
The older version of dhclient that I used kept a lease database. I found 
that I could kick the dates in  the lease database to force the dhcp client 
to renew. 


On 1 Mar 2001, at 13:14, Scott Ehrlich wrote:

> I've actually seen some startup messages flat out tell me my assigned IP,
> which was different than what ifconfig eth0 showed.
> 
> On 1 Mar 2001, Derek Atkins wrote:
> 
> > How do you know that you're not being assigned the same address?
> > DHCP _does_ try to assign the same address when it can.
> >
> > -derek
> >
> > Scott Ehrlich <se at panix.com> writes:
> >
> > > Here's what is happening -
> > >
> > > The PC, when first booted, obtained a DHCP address.  Since that time,
> > > regardless of what I try, has kept the same address.  A few times I did
> > > reboot it, was shown a different IP address during startup, ifconfig still
> > > showed eth0 as the original IP.   At present, no matter what, I still have
> > > that original IP.
> > >
> > > I want to get rid of that address and let the interface dynamically be
> > > assigned whatever address an assignment provides.
> > >
> > > In a similar issue, how do I release and renew a lease?
> > >
> > > Thanks.
> > >
> > > Scott
> > >
> > > On 1 Mar 2001, Derek Atkins wrote:
> > >
> > > > DHCP, by default, wants to renew the same IP Address.  Indeed, unless
> > > > there is a particular reason why, the DHCP server will give you the
> > > > same IP address as well.
> > > >
> > > > I guess I don't understand what you are trying to do.  The DHCP client
> > > > will automatically renew the lease for you.  All you need to do is
> > > > down the interface if you want to disconnect.  There is no supported
> > > > way in the DHCP protocol to 'release' a lease at the server.
> > > >
> > > > -derek
> > > >
> > > > Scott Ehrlich <se at panix.com> writes:
> > > >
> > > > > Hello to all:
> > > > >
> > > > > I have a PC at work onto which I installed Slackware 7.0 and enabled DHCP.
> > > > > I also upgrade the kernel to 2.2.18.   Since doing all this, the dhcp
> > > > > client will not release the IP address it obtained from initial booting.
> > > > > I've tried removing /etc/dhcpc/* except for the .exe script for logging
> > > > > when it detects a new IP address.
> > > > >
> > > > > I've looked at the man pages for dhcp, dhcpcd, and ifconfig, and nothing
> > > > > lets me release the IP address.
> > > > >
> > > > > How can I force the release and force query and acceptance of a new
> > > > > address should a lease or reboot offer address?
> > > > >
> > > > > Thanks.
> > > > >
> > > > > Scott
> > > > >
> > > > > -
> > > > > Subcription/unsubscription/info requests: send e-mail with
> > > > > "subscribe", "unsubscribe", or "info" on the first line of the
> > > > > message body to discuss-request at blu.org (Subject line is ignored).
> > > >
> > > > --
> > > >        Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
> > > >        Member, MIT Student Information Processing Board  (SIPB)
> > > >        URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
> > > >        warlord at MIT.EDU                        PGP key available
> > > >
> > >
> >
> > --
> >        Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
> >        Member, MIT Student Information Processing Board  (SIPB)
> >        URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
> >        warlord at MIT.EDU                        PGP key available
> >
> 
> -
> Subcription/unsubscription/info requests: send e-mail with
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Jerry Feldman <gaf at blu.org>
Associate Director
Boston Linux and Unix user group
http://www.blu.org
-
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