version 15 switch software microcode and NIC card

[gary.pope]

Since upgrading a 3750x switch stack to version 15, PC's on the network do not get a DHCP lease. The only way to get them to work is disable and re-enable the NIC card.

Downgrading the IOS does not downgrade the microcode on the switches.

Is there anyway to downgrade the microcode?

Sent from Cisco Technical Support iPad App

[Reza Sharifi]

What version of IOS did you downgrade to? most newer versions of IOS upgrade the microcode also.

[paolo bevilacqua]

A version what on which switch exactly?

Seems very strange, such a serious issue should be know by Cisco, have you contacted the TAC?

[Leo Laohoo]

I don't agree.  I have upgrade my 3750X to 15.0(1)SE2 and I have not seen this behaviour before.

Microcode upgrades the switch's bootstrap.