Hello i have now 2 WLC, 1 will be backup of the other (1 in the US, the other in europe, both are connected in the network), same version both of them, i need to have the exact same config on each of them.
The one in europe is in prod since few years, the one in the US is the new one (not configured yet).
What is the best way? --> export the conf of the one in prod, and reimport it on the backup one... then change IP@... ? is it the best way to do?
I prefer making a backup and editing the backup and uploading to the new WLC. Sometimes the upload will fail and you will have to edit more than the hostname and the IP's. You will get an error saying the backup failed because of an encryption. The fix is that you might have to delete the usernames and manually enter those in the configuration without being encrypted. This has been something I have had to do recently with the later code versions Also you need to make sure you have a trailing white space at the end of each command or else that command will not take.
If this becomes painful and the code just doesn't upload without an error. Then configure it manually and then when you are done, compare the backup images on both WLC's to make sure you have everything.
Just to note, I never design a backup that would cross any bug body of water. Your best bet is to have two in Europe and two WLC's in the US. You can get an HA sku WLC for cheap and use AP SSO or N+1. These HA sku WLC provide redundancy and are cheaper because they don't require you to purchase licenses.
1 will be backup of the other (1 in the US, the other in europe, both are connected in the network), same version both of them, i need to have the exact same config on each of them.
This is because the regulatory domain of the APs in Europe and US are different. If, for example, your European AP joins the US-based controllers (or vice versa), then either the APs won't join the controllers or the 802.11a/n radios will be disabled.
As Scott has recommended, the best practice is to "bunch up" the APs based on the AP's regulatory domain. So get WLCs for US regulatory domain (-A) and get another set of WLC for Europe (-E).
And by the way, just in case some smart a$$ bean counter should even venture about installing US regulatory domain AP in Europe, I recommend you talk to legal department because this is against the law of the land where the AP will be installed.