Nortel 2000 Using Manual page 34

• Hybrid—This stack has a combination of BPS 2000 switches and BayStack*
450 and/or BayStack 410 switches. It is sometimes referred to as a mixed
stack. The stack operational mode for this type of stack is Hybrid Mode.
When you work with the BPS 2000 in standalone mode, you should ensure that
the stack operational mode shows Pure BPS 2000 Mode, and does not show
Hybrid Mode.
All BPS 2000 switches in the stack must be running the identical version of
software, and all the BayStack switches must be running the identical version of
software.
When you are working with a mixed stack, you must ensure that the
Interoperability Software Version Numbers (ISVN) are identical. That is, the
ISVN number for the BayStack 450 switch and BayStack 410 switch must have
the same ISVN as the BPS 2000. If the ISVNs are not the same, the stack does not
operate.
In sum, the stacking software compatibility requirements are as follows:
• Pure BPS 2000 stack—All units must be running the same software version.
• Pure BayStack 450 stack—All units must be running the same software
version.
• Hybrid stack:
— All BPS 2000 units must be running the same software version.
— All BayStack 410 units must be running the same software version.
— All BayStack 450 units must be running the same software version.
— All software versions must have the identical ISVN.
Refer to Appendix B for complete information on interoperability and
compatibility between the BPS 2000 and BayStack switches.
Using the Business Policy Switch 2000 Version 1.2
34