It is a very good idea but consider moving it farther from where you could anticipate the fire to start. You don't want to be burned reaching for it.
Since I do a lot of fire inspections at work, Undun and the other guys are right and I recommend mounting the fire extinguisher outside of the room either next to the door or near the door you would normally enter the room with. If that is not an option, mounting it just right in the door would be the next best bet. God forbid if something goes kaput, having the extinguisher in hand before entering is a must.
Make sure that extinguisher is an ABC model, by the picture it looks like it may have a slash through the "C" designation, but that could be the picture too. If it is not rated for Class C fires (electrical) grab a ABC or BC (preferable), CO2 extinguishers are also preferable for electronics and electrical. Make sure you also inspect the extinguisher each month to make sure it remains charged and keep up on the special maintenance required. Your local extinguisher / fire protection shop can help out.
If you need any ideas, give me a PM and I'll be more then willing to help out.
Good luck with the patch panel, hope iot works out for yah!!
