On 03/03/2016 at 12:42 PM, Minfei Huang wrote:
> On 03/03/16 at 12:21pm, Xunlei Pang wrote:
>> On 03/03/2016 at 11:40 AM, Minfei Huang wrote:
>>> On 03/03/16 at 10:49am, Xunlei Pang wrote:
>>>> Currently kdump uses dracut's "nameserver=" command to
hande DNS,
>>> handle
>>>> it is acquired both from ifcfg files and "/etc/resolv.conf".
>>>>
>>>> This is improper for dhcp cases, as "/etc/resolv.conf" is
generated
>>>> by dhcp, the proper logic should be:
>>>> 1) For static cases, DNS can be acquired from corresponding ifcfg file.
>>>> 2) For dhcp cases, DNS is normally generated by dhcp, but extra DNS
>>>> can still be specified in the ifcfg files mannually.
>>>> 3) For special user-assigned DNS not specified in any ifcfg file, we
can
>>>> pass it to dracut via "nameserver=".
>>> This patch may cause a regression, since kdump doesn't take care of
>>> /etc/resolv.conf. Kdump kernel cann't get proper DNS, if it is appended
>>> manually in /etc/resolv.conf.
>>>
>>>
https://bugzilla.redhat.com/show_bug.cgi?id=1196085
>> IIRC(I will double check that) I've tested the case that adding manually a
>> DNS entry into /etc/resolv.conf, after reboot the manually added entry will
>> be cleaned up by the system using that in the ifcfg files.
> Yes, /etc/resolv.conf will be re-generated after booting. For production
> environment, it is more convenience to use script to append manual DNS.
Yes, so in my view, we can ignore /etc/resolv.conf completely.
Hmm, I think kdump should handle it as well. For a large number of
machines, it is difficult to configure DNS manually in general.
Thanks
Minfei