System Firmware Version 5.1.0.1  Page 3 
 
Firmware Downgrade 
Downgrading from 5.1.0.1 to an earlier release is supported on most PowerConnect series switches (except PC81xx series 
 with B1 CPU versions, see note below); however, migration of configuration information from a later release to an earlier 
release is not supported. The existing configuration may or may not work with the earlier version of firmware, therefore, it is best 
to be physically present at the switch site and to be prepared to access the switch over the serial port if necessary when 
downgrading firmware. 
 
Auto-downgrade of a stack is not enabled by default. If downgrading a stack, be sure to enable auto-downgrade before activating 
the earlier versions of firmware on the stack master. 
 
Recent versions of the PowerConnect 81xx series switches support newer versions of CPU (B1).  The B1 version of CPU 
requires Release 5.1.0.1 or later firmware and cannot be downgraded to earlier releases. In addition, if this unit is to be deployed 
as a member within a stack, the entire stack will be required to run 5.1.0.1 or later firmware. Here are some steps to help 
determine what CPU is in the PowerConnect 8100 Series switch: 
 
1.  Run show version from the CLI prompt. 
2.  If there is no CPU version line, then the stack is running 5.0.x.x firmware. Since 5.0.x.x can only run on 
A1 CPU switches, then all switches in the stack (or a standalone) contain A1 CPUs. 
3.  If there is a CPU version line (like below): 
CPU Version....................... XLP308H-A1 
(It will display the CPU version in the last two characters - either A1 or B1). 
4.  On a stack, run show version m where m is the unit number assigned to the stack member to see each CPU 
version for each member in the stack. 
 
In addition here are the part numbers for reference: 
 
 
Recent versions of the PowerConnect M8024-K modular switches have hardware changes that require firmware version 4.1.0.19 
or higher. PowerConnect M8024-K with a new PPID label cannot be downgraded below 4.1.0.19. If a downgrade is attempted, 
the firmware activation procedure will detect that earlier firmware is not compatible with the switch hardware and abort the 
activation procedure. Any PowerConnect M8024-K with the old PPID label can accept any version of the switch firmware. 
 
MODEL  OLD PPID  NEW PPID 
M8024K  
2F07F A00   2F07F A01 
57821 A00   57821 A01