I am looking to upgrading IOS on my routers. I haven't done this before and I want to make sure I dont mess this up. I have a 2811 Ver. 12.4(15)T7. I would like to upgrade to the latest version. I have IPSec tunnel on here, some class maps, Nat, ACL,
How do I choose the current and correct version?
Will I need to re-configure the router like nat, ACL,s class maps? How can I verify that?
I am sure, I can't just jump in to the latest version, I am assuming I need to go to the next version all the way to the latest?