SWITCH 300-115 1.5 Configure and verify EtherChannels

1.5.d EtherChannel misconfiguration guard
Etherchannel misconfiguration guard is enabled by default and does what it says it does; helps prevent misconfiguration of etherchannels.
We know that the interfaces we bundle into a channel need to have matching configurations or they will not be suitable, but often enough they are mistakenly put together in a hurry without verifying both sides interfaces first. Etherchannel misconfiguration guard will place the channel in errdissable state and issues an error message if it detects a possible misconfiguration.
To verify that etherchannel guard misconfig is in place as the default use:
sh spann summ | i Ether
If you do break the etherchannel by purposely misconfiguring, or not, you can reenable the channel with shut/no shut or by adjusting the errdisable recovery time interval.