Some comparisons to help you remember easier: RAM is a volatile memory so contents are lost on reload, where NVRAM and Flash contents are not. The bootstrap checks the Configuration Register value to specify where to load the IOS. The IOS attempts to load the configuration file (startup-config) from NVRAM to RAM.
NVRAM holds the startup configuration file, where RAM holds the running configuration file. By default (the default value of Configuration Register is 2102, in hexadecimal), the router first looks for “boot system” commands in startup-config file. If the startup-config is not found in NVRAM, the IOS attempts to load a configuration file from TFTP.
Just got in a new Cisco ISR 4431 and needed to upgrade IOS-XE out of the box.
Cisco has been nice enough to include a 1Gb USB flash drive with their new ISRs, making the software upgrade process a cinch.
The problem is that this isn't something the Borg can just issue a patch for.Update 2011/09 : To update other members in a running stack once you have prepared the master, you must copy and enable the image on each of them as follows : Switch#copy flash1:/c3750-advipservicesk9-mz.122-35. SE5flash2: Destination filename [c3750-advipservicesk9-mz.122-35. As a network engineer, we can garuentee you there will come a point in your career where you must upgrade the Cisco IOS on a Router or Switch.This lab will discuss and demonstrate the upgrade the Cisco IOS update procedure.