What is the best backup battery for 2 routers,6 Cisco switches, 2 servers, and 1 dell md3400 storage device.

As far as brand goes, stick with APC or Tripp-LIte.  I prefer APC simply because of my past history with their customer service (they are pretty amazing), but both are solid brands.

On the servers:

- How many CPUs?
- How many HDDs?
- How many PSUs and what wattage?

Regarding the solution requirements "automatically backup in case of a power surge  and reload configuration after power comes back", can you expand on that a little?

If you want a really good solution, look at these devices:
http://www.apc.com/shop/us/en/products/APC-Symmetra-LX-8kVA-Scalable-to-16kVA-N+1-Rack-mount-208-240V/P-SYA8K16RMP

Far from low end, but the APC Symmetra is a great device that will give you very clean output.  They should be hardwired by the electrician into the panel and that may also help your power issue.   This is a guess on the amount of power you need based on assuming that the 2 servers are just a midrange Dell or HP server. If you have a blade center or something that is a power hog, you need to upgrade.

I also have a client on similar conditions and after a lot of wasted money on standard UPS we found the strongest and most reliable solution which is also scalable,

Power Inverter

Battery 12v100ah

and the best of it? at low cost.

and if you check the watts consumption of each device and post it here, i can give you a hint on how much time you will be without external power supply.

Personally I prefer Eaton. The 5px2200 is a great unit and the top end still only requiring a 20A circuit. If you want more runtime you can add a battery shelf without going to a bigger model.

With any of the brands if you get over 2200va they will need 30A circuits which you probably don't have near your rack.

i would measure the power consumption
if you can easily power down - you can use a kill-a-watt meter : http://www.p3international.com/products/p4400.html

if not use a current clamp like this one (up to 20 A) :  http://www.fluke.com/fluke/then/accessories/current-clamps/i200s.htm?pid=56289

once you have the separate consumption, you can add it up to have an idea of the power needed - you can use this site :  http://www.csgnetwork.com/upssizecalc.html

Most UPSs can trigger shutdown scripts - check out PSshutdown from MS, coupled with the Sleep command, so you can set these to run when the batteries reach a certain level of depletion.

In terms of backups, you should have regular backups in any case, and you'd need to give more info on how these are done at present to see whether they could be triggered automatically to complete during the battery lifespan window that you have.  The network gear should not need any extra backups.

OK. SO here are the specs.

2 servers dual 550 watts. X185V
2 600w power SUpply dell stroage device. NFCGI
1 x CIsco firewall 5515-X  70W
1 x Cisco switches 3750-X  350W
1 x Cisco switch   2960X   740W
1 x Cisco switch   2960x   370w
1 x Cisco switch   2960x   370w
1 x PowerEdge R210 442B3M1 350W

Some of that gear has dual psu so you want two ups on different circuits anyway. I'd go with 2 Eaton 5px2200 and get good runtime.  With the price of that gear, under $3k for 2x ups is pretty reasonable.