dhcpcd-discuss

I tested a version of dhcpcd without the patch (see
https://github.com/raspberrypi/linux/issues/2544#issuecomment-391738783)
and can confirm it resolved my problem.

Did you want me to do a test with some other config?

Jeremy

On 24 May 2018 at 19:32, Serge Schneider <serge@xxxxxxxxxxxxxxx> wrote:

> I've had a look at the patches we apply on top of upstream dhcpcd, and
> this one is likely to be the culprit:
>
> --- a/if.c
> +++ b/if.c
> @@ -534,7 +534,7 @@
>          /* We reserve the 100 range for virtual interfaces, if and when
>           * we can work them out. */
>          ifp->metric = 200 + ifp->index;
> -        if (if_getssid(ifp) != -1) {
> +        if (if_getssid(ifp) != -1 || *ifp->name == 'w') {
>              ifp->wireless = 1;
>              ifp->metric += 100;
>          }
>
> On Thu, May 24, 2018 at 5:42 AM, JED <John@xxxxxxxxxxxxx> wrote:
>
>> Hi, Jeremy. I had the same problem except it worked with 6.11.5 until I
>> did apt-get upgrade and THEN it started to fail, still with 6.11.5. I never
>> did figure out what changed to break it.
>>
>> What I did to resolve the issue is a workaround on a later version so I
>> had RPi 3 B+ support. I went back to the /etc/network/interfaces
>> configuration method and turned off dhcpcd. My GUESS is that dhcpcd is
>> "waiting for carrier" because when I send it "dhcpcd -n wwan0" it again
>> says "waiting for carrier" but the "interfaces" method SEEMS to just look
>> for something else and its dhcp does the job, looking at the interface
>> every 5 minutes and completes the dhcp so that ifconfig wwan0 shows the
>> correct stuff that modem manager logged when the modem was connected. From
>> then on, everything works great. Also, I can issue a command and make it
>> happen without waiting for the 5 minutes.
>>
>> I've just come to this conclusion and NEVER asked Roy about it since we
>> exchanged messages early last month, so he's not had a chance before to
>> comment on my Wild A** Guess.
>>
>> I'm in the North Woods(tm) planting 1,000 pine trees and can't access the
>> "whatIdid" file on that particular RPi from here since it's powered down,
>> so I can't give you specifics of my configuration files or the commands
>> that I use to speed things up. They do work on my latest Raspbian copy that
>> started with a 2018-04-18-raspbian-stretch download. I'll be home this
>> weekend and if Roy hasn't helped by then I'll send you what works for me.
>>
>> On 5/23/2018 7:05 PM, Jeremy K wrote:
>>
>>> I'm running Raspbian on the Raspberry Pi and have been encountering DHCP
>>> issues with my USB 3G modem.
>>>
>>> The previous discussion for this issue is here
>>> https://github.com/raspberrypi/linux/issues/2544, but to summarise,
>>> dhcpcd 6.10.1 works as expected, but dhcpcd 6.11.5 does not.
>>>
>>> The modem driver (sierra_net) exposes a wwan0 interface, and on dhcpcd
>>> 6.10.1, the interface successfully gets the IPv4 address and the interface
>>> works as expected.
>>>
>>> Using dhcpcd 6.11.5, the wwan0 interface does not get an IP address, so
>>> I can't use it. If I downgrade back to 6.10.1, then the interface gets the
>>> IP address and starts working again.
>>>
>>> Here is the syslog snippet using 6.10.1 (good)
>>>
>>> |Sep 7 15:54:40 raspberrypi dhcpcd[250]: wwan0: waiting for carrier Sep
>>> 7 15:54:40 raspberrypi kernel: [ 21.042350] IPv6: ADDRCONF(NETDEV_UP):
>>> wwan0: link is not ready Sep 7 15:54:41 raspberrypi systemd[1]: Started
>>> Raise network interfaces. Sep 7 15:54:42 raspberrypi kernel: [ 22.660424]
>>> IPv6: ADDRCONF(NETDEV_CHANGE): wwan0: link becomes ready Sep 7 15:54:42
>>> raspberrypi dhcpcd[250]: wwan0: carrier acquired Sep 7 15:54:42 raspberrypi
>>> dhcpcd[250]: wwan0: adding address fe80::1e09:995:5f42:fa48 Sep 7 15:54:43
>>> raspberrypi dhcpcd[250]: DUID 00:01:00:01:21:44:28:43:26:46:ee:43:01:07
>>> Sep 7 15:54:43 raspberrypi dhcpcd[250]: wwan0: IAID ee:43:01:07 Sep 7
>>> 15:54:43 raspberrypi dhcpcd[250]: wwan0: soliciting a DHCP lease Sep 7
>>> 15:54:43 raspberrypi dhcpcd[250]: wwan0: soliciting an IPv6 router Sep 7
>>> 15:54:43 raspberrypi dhcpcd[250]: wwan0: offered 100.113.23.172 from
>>> 100.113.23.253 Sep 7 15:54:43 raspberrypi dhcpcd[250]: wwan0: probing
>>> address 100.113.23.172/32 <http://100.113.23.172/32>|
>>>
>>> and the same for 6.11.5 (bad):
>>>
>>> |Nov 29 02:37:27 raspberrypi dhcpcd[238]: wwan0: waiting for carrier Nov
>>> 29 02:37:27 raspberrypi dhcpcd[238]: wwan0: carrier acquired Nov 29
>>> 02:37:27 raspberrypi dhcpcd[238]: wwan0: IAID 17:fa:01:07 Nov 29 02:37:27
>>> raspberrypi dhcpcd[238]: wwan0: adding address fe80::3cc3:cfbd:f6e4:82ec
>>> Nov 29 02:37:27 raspberrypi dhcpcd[238]: wwan0: carrier lost Nov 29
>>> 02:37:27 raspberrypi dhcpcd[238]: wwan0: deleting address
>>> fe80::3cc3:cfbd:f6e4:82ec |
>>>
>>>
>>> Can anyone help me to figure out why 6.11.5 isn't working as expected,
>>> and if there is a configuration I can change to resolve the issue?
>>>
>>>
>>> Regards,
>>>
>>> Jeremy
>>>
>>>
>>
>