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Cisco Catalyst Blade Switch 3120 for HP Command Reference
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Chapter 2 Cisco Catalyst Blade Switch 3120 for HP Cisco IOS Commands
sdm prefer
•
If a stack member cannot support the template that is running on the master switch, the switch goes
into SDM mismatch mode, the master switch does not attempt to change the SDM template, and the
switch cannot be a functioning member of the stack.
For more information about stacking, see the “Managing Switch Stacks” chapter in the software
configuration guide.
Use the
no sdm prefer
command to set the switch to the default desktop template.
The access template maximizes system resources for access control lists (ACLs) as required to
accommodate a large number of ACLs.
The default templates balances the use of system resources.
Use the
sdm prefer vlan
global configuration command only on switches intended for Layer 2
switching with no routing. When you use the VLAN template, no system resources are reserved for
routing entries, and any routing is done through software. This overloads the CPU and severely degrades
routing performance.
Do not use the routing template if you do not have routing enabled on your switch. Entering the
sdm
prefer routing
global configuration command prevents other features from using the memory allocated
to unicast routing in the routing template.
Do not use the ipv4-and-ipv6 templates if you do not plan to enable IPv6 routing on the switch. Entering
the
sdm prefer ipv4-and-ipv6
{
default
|
routing
|
vlan
} global configuration command divides
resources between IPv4 and IPv6, limiting those allocated to IPv4 forwarding.
Table 2-15
lists the approximate number of each resource that is supported in each of the IPv4-only
templates for a desktop switch. The values in the template are based on 8 routed interfaces and
1024 VLANs and represent the approximate hardware boundaries set when a template is selected. If a
section of a hardware resource is full, all processing overflow is sent to the CPU, seriously impacting
switch performance.
Table 2-15
Approximate Number of Feature Resources Allowed by IPv4 Templates
Resource
Access
Default
Routing
VLAN
Unicast MAC addresses
4 K
6 K
3 K
12 K
Internet Group Management Protocol
(IGMP) groups and multicast routes
1 K
1 K
1 K
1 K
Unicast routes
6 K
8 K
11 K
0
•
Directly connected hosts
4 K
6 K
3 K
0
•
Indirect routes
2 K
2 K
8 K
0
Policy-based routing access control entries
(ACEs)
0.5 K
0
0.5 K
0
Quality of service (QoS) classification ACEs 0.5 K
0.5 K
0.5 K
0.5 K
Security ACEs
2 K
1 K
1 K
1 K
VLANs
1 K
1 K
1 K
1 K
