Alcatel-Lucent OmniSwitch 6850-48 Hardware User's Manual page 162

Reloading Switches
No Switches In the Stack Have Saved Slot Information
If a full reload is issued and no switches in the stack have unique slot numbers, slot numbers will be
assigned beginning with the switch with the lowest MAC address. (This can occur if the boot.slot.cfg file
has been deleted from each switch's /flash directory—e.g., by issuing the
modules in the stack.)
The switch with the lowest MAC address is assigned slot number 1 and given the primary management
role. The switch connected to stacking port A of the primary switch is automatically assigned slot
number 2 and given the secondary management role. Stack cabling is then used to determine the dynamic
slot numbering of the remaining modules in the stack. The switch immediately adjacent to slot 2 is
assigned slot number 3 and given an idle role, etc.
An illustrated example of this method for assigning slot numbers and management roles is provided on
pages 4-20 and 4-21.
Some Switches Have Saved Slot Information, Others Do Not
If only some switches in the stack have boot.slot.cfg files in their /flash directories, the system software
will first read the contents of these files and then dynamically assigns unique slot numbers to any switches
that do not have saved slot information. The primary management role will be given to the switch with the
lowest saved slot number. The secondary management role will be given to the switch with the second-
lowest saved slot number. All other switches will be assigned to idle roles.
When unique slot numbers are dynamically assigned by the system software, a boot.slot.cfg file is auto-
matically generated with the new slot information. Because all switches now have unique saved slot infor-
mation, any subsequent reload all commands issued will cause the stack to come up as described in the
section, "All Switches Have Unique Saved Slot Information" on page
Two or More Switches Have Duplicate Slot Information
If a full stack reboot is issued and the same slot number is found in the boot.slot.cfg file of two or more
switches, the switch with the lowest MAC address is allowed to come up and operate normally. Mean-
while, any other switches with the duplicate slot number come up in pass-through mode.
The pass-through mode is essentially an error state in which a switch has been denied primary, secondary,
and idle roles within the stack. When a switch is in pass-through mode, its Ethernet are brought down and
cannot pass traffic. It is for this reason that users should always check the current saved slot number for
each switch before issuing the reload all command. To check the current saved slot information across the
stack, use the show stack topology
"Pass-Through Mode" on page
page 4-32
command. For detailed information on pass-through mode, refer to
4-12.
OmniSwitch 6850 Series Hardware Users Guide
Managing OmniSwitch 6850 Series Stacks
stack clear slot command for all
4-31.
September 2009