Today, when I logged into the devices I had to erase all the configuration and reload the devices AGAIN. It took me from 15 to 20 minutes in order to erase all the configuration, reload all the devices and apply the basic configuration so I could start working on the lab. At the end of my session, I took the last 10 minutes to erase all the configuration and reload the devices. I had scheduled the lab for two hours...so I spent around 30 minutes (25% of all the time I had...) power cycling devices, etc. It's okay to spend the last 10 minutes in order leave the lab in good condition for the next person to use it as I would like to get it. However, IT IS NOT okay to spend all that time doing something someone else should have done.

I wonder if it is that hard being at least polite and erasing all the configuration and reloading the devices as the instructions of use of the lab states. The same way it's free of charge for you and a great opportunity it's also for me...so we should have the same rights and duties. From the times I used the lab I got all the devices ready for use only ONCE!

One of the things I'm currently testing in my lab is using configuration rollback. Basically, every router and switch has a file in flash called default.cfg. This file was simply a copy of the default startup config immediately after the device was wiped. My students simply enter the privileged EXEC command:

configure replace flash:default.cfg

when they are finished with the lab. This essentially reverts the entire configuration back to the blank config. It's different than

copy flash:default.cfg run

because that command merges the current running config with the default.cfg file, whereas configure replace actually removes the current running config completely, then copies the default.cfg file.

It takes roughly 5 seconds to complete (depending on how much configuration has to be removed) and requires no restart. It will issue the "shutdown" command on interfaces, remove passwords, and even removes loopbacks and subinterfaces.

I've only been testing it a short time, but so far it works really well. The only thing it can't do is delete the vlan.dat file and remove VLANs, so that's still a manual process. As long as nobody deletes or modifies the default.cfg file though, this can be a huge time saver. You may even be able to implement a script on the console server that can run the command for you after the user is disconnected.

Hope that helps. Even if you don't decide to implement it for all users, maybe some users can make use of it to make switching between configurations faster.