====== Restart USB device ======

I'm using external usb mouse on keyboard with and Debian Jessie Linux and it does not work after reboot.
All I have to do is unplug and insert the mouse and keyboard again. (Reinsert) 
The same thing happens on two out of three totally different computers.

<code bash>
isa@misaThinkpad:~$ uname -a
Linux misaThinkpad 3.16-3-amd64 #1 SMP Debian 3.16.5-1 (2014-10-10) x86_64 GNU/Linux
</code>

I can simulate the reinsertion by this script

<code bash>
# reseting USB2 ports
for i in $(ls /sys/bus/pci/drivers/ehci-pci/|grep :)
 do echo $i >/sys/bus/pci/drivers/ehci-pci/unbind
 echo $i >/sys/bus/pci/drivers/ehci-pci/bind
done
</code>

To have it done every time I start/restart a computer I place it in a file **/etc/profile.d/restart_all_usb_devices.sh** so it is  run automatically.

====== Debian Jessie freezes while booting ======

[[http://www.itwire.com/opinion-and-analysis/open-sauce/65478-from-next-release-onwards-debian-is-tied-to-systemd|Debian Jessie uses by default systemd not SysVinit]] which apart from speeding up the boot process may cause your system to lock up when booting. 
In case you experience this problem [[http://www.itwire.com/business-it-news/open-source/65684-debian-leader-says-users-can-continue-with-sysvinit|you may prefer to keep to use older SysVinit which is also possible to use with Debian Jessie]]

When I have installed packages **sysvinit-core systemd-shim** my problem with system lock up during boot has disappeared.

Also I recommend to remove the word "quiet" from your grub Linux boot options.  You want to know what happened when your computer hangs.

[[https://wiki.debian.org/systemd|More about troubleshooting Systemd can be found on debian Wiki.]]