On Jul 8, 2014, at 1:22 PM, Les Mikesell <lesmikesell@xxxxxxxxx> wrote:
> On Tue, Jul 8, 2014 at 1:08 PM, John R Pierce <pierce@xxxxxxxxxxxx> wrote:
>> On 7/8/2014 6:53 AM, Ned Slider wrote:
>>> That's not always true.
>>>
>>> Some configs that were under /etc on el6 must now reside under /usr on el7.
>>>
>>> Take modprobe blacklists for example.
>>>
>>> On el5 and el6 they are in/etc/modprobe.d/
>>>
>>> On el7 they need to be in/usr/lib/modprobe.d/
>>>
>>> If you install modprobe blacklists to the old location under el7 they
>>> will not work.
>>>
>>> I'm sure there are other examples, this is just one example I've
>>> happened to run into.
>>
>> this is insane. traditionally in Unix-like systems, /usr is supposed
>> to be able to be read only and sharable between multiple systems, for
>> instance in NFS boot scenarios. /var is specifically for host-specific
>> complex configuration and status stuff like /var/logs /var/state
>> /var/run and so forth.
>
> And more to the point, /usr isn't supposed t be needed until you are
> past the point of mounting all filesystems so you can boot from
> something tiny. Doesn't modprobe need its files earlier than that?
This work is all about being able to boot a system with just a read-only /usr. Any foo you need to get to a complex filesystems, like NFS or encrypted software RAID needs to be in the initial ramdisk which the boot loader can access before the kernel loads and which tools like Dracut build based on what’s required for your particular setup. The seeds of that change basically existed from the time that initial ram disks were introduced as a feature a long time ago, now we’ve just widely acknowledged this reality.
—
Mark Tinberg, System Administrator
Division of Information Technology - Network Services
University of Wisconsin - Madison
mtinberg@xxxxxxxx
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
http://lists.centos.org/mailman/listinfo/centos
