I think we are on to something!

On 12/03/2013 09:41 PM, ~Stack~ wrote:
> On 12/03/2013 09:16 PM, ~Stack~ wrote:
>> On 12/03/2013 08:37 PM, Nico Kadel-Garcia wrote:
>>> On Tue, Dec 3, 2013 at 6:36 PM, ~Stack~ <[log in to unmask]> wrote:
>>>> On 12/01/2013 10:36 AM, olli hauer wrote:
>>>>> Have you tried 'service network restart'? Does that bring up your nic?
>>>>
>>>> Well now. That is interesting. This is consistent even with a fresh
>>>> kickstart install.
>>>> $ service network restart
>>>> Shutting down interface eth0:      [  OK  ]
>>>> Shutting down loopback interface:  [  OK  ]
>>>> Bringing up loopback interface:    [  OK  ]
>>>> Bringing up interface eth0:
>>>> Determining IP information for eth0... failed; no link present.  Check
>>>> cable?  [FAILED]
>>>> $ ifup eth0
>>>> Determining IP information for eth0... done.
>>>>
>>>> Errr...what? *scratches head* What exactly is 'ifup eth0' doing that
>>>> 'service network restart' isn't?
>>>
>>> It's running significantly later. Even dumb switches, and supported
>>> network drivers, can tike time to recognize  the available MAC
>>> address. This is especially the case with DHCP, which requires
>>> communications all the way upstream to whatever DHCP server is in
>>> place.
>>
>> The weird part for me is that this is after the box is booted and I have
>> logged in. When I manually run 'service network restart' it fails in the
>> same way _every_ time. Then as soon as I run 'ifup eth0' it works! I
>> think I am going to experiment with this a bit.
> 
> Also, I have been tinkering with this a bit. In /etc/init.d/functions on
> line ~536 (I have been editing a bit but I think that is right) there is
> a line like this in the action function:
> "$@" && success $"$STRING" || failure $"$STRING"
> 
> When I dumped out the variables it is just running './ifup eth0' but it
> is on this line that everything seems to choke. What I find odd though is:
> * If I run it on the command line it works. Running it as a service, it
> fails. Thus I am wondering if it is an environmental variable setting?
> That is my next investigation.
> 
> * If I run 'ifup eth0', get a IP, I can run 'service network restart'
> and get an IP! If I run 'ifdown eth0' or reboot then the service kicks
> back the error about a missing cable (which is obviously wrong).
> 
> Very very odd.

I checked out the environment variables, that is not it. I tried a few
other things and nothing. I don't understand why running '/sbin/ifup
eth0' but in the service command it doesn't work.

So I just started adding '/sbin/ifup eth0' statements into the start
command till it worked. I tweaked it and to reliably get a DHCP IP (even
on reboot!) just add *two* copies of the ifup command in the start
section. I put mine at the end just before the ";;" of the "start)" case
section. One copy alone will not do it. Thus the command is essentially
called three times in a row.

So there *is* a timing issue going on and just hammering it will
eventually get it to work. Now to find the best place to put the timing
delay...

Thanks!