On 02/25/2015 03:43 PM, Josh Boyer wrote:
On Wed, Feb 25, 2015 at 9:35 AM, Ali AlipourR
<alipoor90(a)gmail.com> wrote:
>>> Why sysrq is limited to only "sync" command on official fedora
kernel?
>>
>> The kernel itself isn't limited. It's just set that way in
>> /usr/lib/sysctl.d/50-default.conf which is provided by systemd. You
>> can edit that file, create your own in /etc/sysctrl.d/, or (as root)
>> set it to whatever you would like via /proc/sys/kernel/sysrq.
>
> Of course it can be changed at runtime, but I mean why official fedora
> kernel shouldn't be configured to allow all (or at least a wider
> subset) of sysrq commands by default?
Maybe we're getting hung up on a terminology issue, but this isn't a
kernel configuration issue. It's something userspace is doing.
> This way official fedora live CDs are unsuitable for system recovery
> tasks; you have to change sysrq value every time you use live CDs or
> build your own live CD.
That's a good point. Since the live images have a "rescue" mode,
maybe there is a way to use a different value when booted into that.
How that would look, I'm not sure. Maybe dracut would need to include
an override file in the initramfs.
I don't follow the reasoning. Why am I more likely to need SysRq in
rescue mode than in normal boot?
Michal