[SOLVED - at least my problems] dhcpcd problems

Question

<edit>
I am marking this thread as solved, as the probem I posted about has been solved - thanks to GerBra in his post below (it's post #15).
Once again; my problem was about not being able to get a zeroconf IP address when booting without an ethernet cable attached, and subsequently not getting a dhcp address when connecting a cable after boot-up.
I have always been able to get an ip address (and connecting) when booting with a cable attached.
Therefore I mark this thread as solved.
</edit>
So yesterday I did a system upgrade and got a new kernel (2.6.27-2), new dhcpcd (4.0.2-1), new netcfg (2.1.2-1) plus some other stuff.
If I with the new dhcpcd boots up the machine and doesn't have a network cable connected, I am not getting any IP address at all - whereas before I used to get an address in the 169 range.
That's not such a big deal, but what is worse is that if I then - (after bootup with no cable) - connect a network cable I'm not receiving an IP address at all from the dhcp server. I need to do a /etc/rc.d/network restart to receive a dhcp address!
By downgrading to dhcpd 3.2.1-1 it works OK: I get an 169 range IP address without cable and when connecting a cable I automatically get an IP address from the dhcp server. (Downgrading dhcpcd also requires a downgrade of netcfg if I want to use netcfg2 for example, but that is a topic for another post.)
Can anyone shed any lights on this problem?
Thanks
Niels
Last edited by nielsb (2008-10-19 09:12:37)

Answer 1

handy wrote:
I find this problem very interesting, there are three different solutions that I am aware of:
1.) Downgrade dhcpcd
2.) Downgrade kernel & dhcpcd (by necessity)
3.) Use the following code:
echo 0 >/proc/sys/net/ipv4/tcp_sack
echo 0 >/proc/sys/net/ipv4/tcp_dsack
It would seem that we are all experiencing very similar symptoms, though I'm starting to wonder if we have more than one problem causing these symptoms?
OK, seeing as I started this thread, let me weigh in here:
My problem was NOT, with getting a connection to the network IF my ethernet cable was attached at startup. In that scenario it worked just fine - no problems what so ever.
My problem, which this post was originally about - was about not being able to get a zeroconf IP address (169 range) when booting  without an ethernet cable attached, and subsequently not receiving a dhcp address when connecting an ethernet cable. This problem is solved - thanks to GerBra (post #15) - by deleting the -L flag in /etc/conf.d/dhcpcd and adding the -K flag. If I don't want zeroconf IP address but still be able to pick up a dhcp address when connecting you add the -b flag. Based on this I will now mark this post as solved.
However I do realize that there are/may be other problems with dhcpcd (exactly as handy observes above), which are discussed in this thread. I suggest we start a new thread regarding those issues.
Niels
Last edited by nielsb (2008-10-19 09:13:21)