Change Config-Register

[irbk]

I had 700+ days of uptime on my DR router, so I rebooted my DR router last week Friday and it did not go well.  Ended up coming up in a factory-default state, even though I know I've saved the config multiple times.  Today I got a chance to dig into it and I find that the config register is 0x41, which explains why the system didn't boot the startup config.  According to this knowledge base article it's easy enough to reset, just need to issue 
Router(config)#config-register <whatever>
So 3 questions
1. Will running the config-register command break anything on a running ASA? 
2. What should a "normal" configuration register be?  On my currently normal running primary device (and several other google searches) a config register of 0x1 seems to be "normal" but I wanted to verify.
3. Do I set that via "config-register 0x1" or "no config-register" and does that take effect immediately?  IE, I don't have to worry about it rebooting to factory default or will the next reboot be factory defaulted as well?

TIA!

[balaji.bandi]

what model of the router and ios code running here ?

check what config reg to use :

https://www.cisco.com/c/en/us/support/docs/routers/10000-series-routers/50421-config-register-use.html

[irbk]

Sorry, I should have mentioned that bit of info.  ASA 5525 running 9.14(3).

[balaji.bandi · Accepted solution]

The default configuration register value is 0x1

Load the default configuration by entering the following command:

ciscoasa(config)# no config-register 

and save the config :

# copy running-config startup-config