Every time I was re-booting my video devices changed numbers. Not such a big deal unless you run mythtv and Zoneminder on a dedicatred video box with 8 video inputs from various cards. Zoneminder and mythtv kept getting misdirected on every re-boot. It wasn't often so I lived with it for a while.
I finally had enough and fixed it by writing some udev rules for the video devices. I used the following email ( http://www.mythtv.org/pipermail/mythtv-users/2006-November/157481.html ) as a guide.
It uses a small script (see the right text box) that figures out the varying number to append to the device and the actual udev rules in the /etc/udev/rules.d directory to recognize my different cards and link them to a static name that never changes after a re-boot.
I have 4 video cards
#udevinfo -a -p /class/video4linux/videoN
replace N with the vid number you want info on
This gives you all the details to use in the udev rules to specifically recognize the individual cards.
Once the cards are recognized by the rule, the rule calls the script in the box above to create the symblic link.
Here are my 4 udev rules I added to my /etc/udev/rules.d directory.
Note the filename numbering... They are run in sequential order.
Magically this results in my video devices showing up with a static symbolically linked name that mythtv and zoneminder can use every time!
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