Cisco Catalyst 4500 series Administration Manual page 224

Understanding Virtual Switching Systems
Asymmetric chassis support
Catalyst 4500 and Catalyst 4500X VSS require the same supervisor engine type in both chassis. The
chassis can differ in type (i.e., +E and -E chassis can be in a single VSS) and also can differ in the number
of slots in chassis. VSS cannot be formed between different flavors of Catalyst 4500X (e.g., 4500X-16
and 4500X-32).
Interface Naming Convention
In VSS mode, interfaces are specified using the switch number (in addition to slot and port), because the
same slot numbers are used on both chassis. For example, the interface 1/5/4 command specifies port 4
of the switching module in slot 5 of switch 1. The interface 2/5/4 command specifies port 4 on the
switching module in slot 5 of switch 2.
Module Number Convention
IOS treats modules in both chassis as if they belong to one single chassis and the module number space
is 1-20.
Switch 1 receives a module number from 1-10 and switch 2 receives a number from 11-20, irrespective
the chassis type, supervisor type, or number of slots in a chassis. For example, on a 3-slot chassis VSS,
the module numbers on switch 1 would be 1, 2, and 3, and on switch 2, the numbers would be 11, 12,
and 13. The module number on switch 2 always starts from 11.
The show switch virtual slot-map command provides virtual to physical slot mapping. The following
is a sample output:
Virtual
Slot No
---------+-----------+----------+----------
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Key Software Features not Supported on VSS
With some exceptions, the VSS maintains feature parity with the standalone Catalyst 4500 or 4500-X
series switches. Major exceptions include:
•
•
•
Software Configuration Guide—Release IOS XE 3.6.0E and IOS 15.2(2)SG
5-8
Remote Physical
Switch No Slot No
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
CFM D8.1
Dot1q Tunnel ("legacy/classic" dot1q tunnel)
Dot1q tunneling and L2PT (Layer 2 Protocol Tunneling)
Module
Uptime
1 00:24:14
2 00:23:46
3 -
4 -
5 -
6 -
7 -
8 -
9 -
10 -
1 00:22:03
2 00:24:43
3 00:24:43
4 -
5 -
6 -
7 -
8 -
9 -
10 -
Chapter 5 Configuring Virtual Switching Systems
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