Cisco Catalyst 6880-X Specifications download pdf (Page 70)

Distribution Layer April 2014

Step 13: Configure a synchronized clock by programming network devices to synchronize to a local NTP server

in the network. The local NTP server typically references a more accurate clock feed from an outside source.

Configure console messages, logs, and debug output to provide time stamps on output, which allows cross-

referencing of events in a network.

ntp server 10.4.48.17

ntp update-calendar

clock timezone PST -8

clock summer-time PDT recurring

service timestamps debug datetime msec localtime

service timestamps log datetime msec localtime

The ntp update-calendar command configures the switch to update the hardware clock from the ntp time

source periodically. Since not all switches have a hardware clock, this command is not supported by all devices.

Procedure 3 Configure distribution global settings

Step 1: Configure BPDU Guard globally to protect PortFast-enabled interfaces.

In some scenarios, a service appliance that requires spanning-tree portfast may be connected to the

distribution layer. When an interface is set for portfast, BPDU guard protects against an accidental connection of

another switch into a PortFast-enabled interface, which could cause a catastrophic undetected spanning-tree

loop.

If a PortFast-configured interface receives a BPDU, an invalid configuration exists, such as the connection of

an unauthorized device. The BPDU guard feature prevents loops by moving a nontrunking interface into an

errdisable state when a BPDU is received on an interface when PortFast is enabled.

Disable the interface if another switch is plugged into the PortFast-enabled interface.

spanning-tree portfast bpduguard default

On the Cisco Catalyst 6500 and Catalyst 6800 Series Switches, the global BPDU Guard command is slightly

different.

spanning-tree portfast edge bpduguard default

Step 2: Configure an in-band management interface.

The loopback interface is a logical interface that is always reachable as long as the device is powered on and

any IP interface is reachable to the network. Because of this capability, the loopback address is the best way to

manage the switch in-band. Layer 3 process and features are also bound to the loopback interface to ensure

process resiliency.

The loopback address is commonly a host address with a 32-bit address mask. Allocate the loopback address

from the IP address block that the distribution switch summarizes to the rest of the network.

interface Loopback0

ip address [ip address] 255.255.255.255

ip pim sparse-mode

The need for the ip pim sparse-mode command will be explained further in Step 3 of Procedure 5, “Configure

IP Multicast routing”.

1 2 ... 65 66 67 68 69 70 71 72 73 74 75 ... 110 111

No comments

Cisco Catalyst 6880-X Specifications Page 70