Specifications

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Cisco MGX 8800/8900 Series Software Configuration Guide
Release 5.1, Part Number OL-6482-01, Rev. A0, January 25, 2005
Chapter 1 Preparing for Configuration
Guidelines for Creating a Network Clock Source Plan
Figure 1-5 Using Multiple IP Addresses for Switch Access
The configuration shown in Figure 1-5 provides the following results:
• Direct access to the active PXM using address B.B.B.B.
• Direct access to the standby PXM card using address A.A.A.A.
• The boot code on the standby PXM card can be upgraded without interrupting service on the active
PXM card.
• You can perform additional procedures in backup boot mode on the standby card without
interrupting the active card. These procedures include hard disk formats and file transfers.
When different IP addresses are used for the boot and disk IP addresses, you can manage the active PXM
card and the switch using the disk IP address, which is B.B.B.B in Figure 1-5. You can also access the
standby PXM card using the boot IP address. When the same address is used for both the boot and disk
IP addresses, that address can be used only to manage the active PXM card.
When planning IP addresses for your switch, use the following guidelines:
• If the switch has one PXM, make the boot and disk IP addresses the same.
• If the switch has two PXM cards and you want to minimize the number of IP addresses used, set
both boot IP addresses and the disk IP address to the same address.
• If the switch has two PXM cards and you want to maximize your control options from remote
locations, assign the same boot IP address to each PXM card, and assign a different IP address to
the disk IP address.
• Be sure to define the default gateway IP address when defining the boot IP addresses.
• To minimize router configuration, choose boot, LAN, and default gateway IP addresses that are all
on the same subnet.
For instructions on setting boot and disk IP addresses, see the “Setting the LAN IP Addresses” section
in Chapter 2, “Configuring General Switch Features.”
Guidelines for Creating a Network Clock Source Plan
Clock synchronization in an ATM network is very important. If two switches have trouble synchronizing
their communications, traffic between the switches may have excessive errors or line failures. MGX
switches support two methods of network clock synchronization:
• Manual
• Network Clock Distribution Protocol (NCDP)
Both of these methods of clock synchronization are described in the sections that follow.
Boot IP
address:
A.A.A.A
Boot IP
address:
A.A.A.A
Slot 1 PXM Slot 2 PXM
66395
Disk IP address: B.B.B.B