Re: dhcpcd timeout

[Victor Gaydov <victor gaydov gmail com>]

On Tue, 22 Jun 2010 01:21:29 -0700
Dan Williams <dcbw redhat com> wrote:

> On Fri, 2010-06-11 at 12:42 +0400, Victor Gaydov wrote:
> > On Fri, 04 Jun 2010 19:23:55 -0700
> > Dan Williams <dcbw redhat com> wrote:
> > 
> > > On Thu, 2010-06-03 at 10:34 +0400, Victor Gaydov wrote:
> > > > Hello,
> > > > 
> > > > After upgrade from 0.7 to 0.8 NetworkManager compiled with
> > > > dhcpcd can't start connection because of dhcpcd timeout. Is it
> > > > a way to change this timeout?
> > > > 
> > > > Notes:
> > > >  - NetworkManager compiled with dhclient works fine
> > > >  - dhcpcd executed manually work fine
> > > >  - it seems that lease-time from /etc/dhcp/dhcpd.conf doesn't
> > > > matter when dhcpcd is executed by NM
> > > > 
> > > > Log attached.
> > > 
> > > Is there any chance you could run wireshark on the interface and
> > > see if any DHCP packets get out?  This is quite odd and it would
> > > point to either a misconfiguraton of dhcpcd on NM's part (maybe
> > > sendign the wrong command-line arguments) or it could point to a
> > > problem in dhcpcd.  It might also be useful to strace dhcpcd to
> > > see what it's doing.
> > > 
> > > The logs show the problem, but don't really provide any insight
> > > into what might be going on.  The other alternative may be to
> > > recompile NM and send any debugging or verbose command-line
> > > arguments that dhcpcd might use to get more output from it about
> > > the issue.
> > > 
> > > Dan
> > > 
> > > 
> > 
> > Hello! Sorry for delay.
> > 
> > The problem was related to timeouts: 45s is not enough. I changed
> > DHCP_TIMEOUT in sources and added '-t' option to dhcpcd and
> > everything works fine. Is it a way to change dhcp timeout in config
> > file?
> > 
> > PS. Debug log is attached. I can also send wireshark log if
> > necessary - yes, DHCP packets are getting out.
> 
> So in this case the server is just very, very slow to respond?  Is the
> network heavily loaded?  Or is the DHCP server heavily loaded?  I'm
> not really opposed to upping the timeout by a small amount, but if
> the DHCP server isn't responding within a certain timeframe, there's
> clearly something wrong with the network, whether that timeframe is
> 45 seconds, 60 seconds, or whatever.  At this point, upping the
> timeout isn't really guaranteed to fix the problem anyway if it's
> this bad already...
> 
> What DHCP timeout worked for you?
> 
> Dan
> 
> 
> 

Timeout varies from 30 seconds to a minute. It is desktop computer and
ADSL modem; provider is "stream" (http://www.stream.ru). Dhclient sends
a few (about 3 of 4) queries before server responds.

I can provide any details, if necessary, but in any case I'm not able
to configure anything except client side. I think NetworkManager's
restrictions looks quite artificial: yes, it may be something
wrong with network, but it's more flexible to allow user to configure
it by himself.. Anyway, NM compiled with dhclient works fine, so there
are no problems for me.

-- 
Victor Gaydov.