[lug] RHEL6 USB and network issue

[Michael J. Hammel]

On Wed, 2013-11-13 at 14:13 +0000, stimits at comcast.net wrote:
> Where do I truly want to edit to have my echo to various sys
> parameters and have the change survive reboots (especially on fedora,
> though I doubt it matters)? 

I'm still using /etc/rc.d/rc.local.  If you create a shell script there
and enable the rc-local service it will pick up your changes on reboot.
Heck of a lot easier than tracking down the myriad of specialized
configuration files.

Here's a discussion on using rc.local to set video driver
configurations:
https://ask.fedoraproject.org/question/9102/where-in-systemd-to-put-an-initialization-hack/

I use it on my VM hosts and guests to change the device timeout on scsi
drives:

for i in /sys/class/scsi_generic/*/device/timeout; do echo 180 > "$i";
done

The default of 30 was causing /home to get remounted as RO.
> 
> Is there an intuitive rule to figure out what a config line would be
> from /sys if we do not look at /proc?
> 
$ find /sys/module -name "*autosuspend*"
/sys/module/usbcore/parameters/autosuspend

If you don't know to look under module just do /sys.  You get a lot more
stuff so you can pipe it through "grep parameters" to whittle it down a
bit.  

If you're trying to configure a driver then you usually want the
parameters entry under its module name.  However, I can't guarantee that
this entry is read-write - it may be read-only.  And I can't guarantee
that the module parameter will be what you're looking for, as in the
case of the scsi timeout (which I found with a Google search).

So my answer would be "no, there isn't an intuitive rule" but I managed
to find what I needed anyway.
-- 
Michael J. Hammel <mjhammel at graphics-muse.org>