BLADE OS™ Application Guide HP GbE2c Ethernet Blade Switch for c-Class BladeSystem Version 5.1 Advanced Functionality Software
Table Of Contents
- Contents
- Figures
- Tables
- Preface
- Part 1: Basic Switching
- Accessing the Switch
- The Management Network
- Local Management Using the Console Port
- The Command Line Interface
- Remote Management Access
- Client IP Address Agents
- Securing Access to the Switch
- Setting Allowable Source IP Address Ranges
- RADIUS Authentication and Authorization
- TACACS+ Authentication
- LDAP Authentication and Authorization
- Secure Shell and Secure Copy
- Configuring SSH/SCP Features on the Switch
- Configuring the SCP Administrator Password
- Using SSH and SCP Client Commands
- SSH and SCP Encryption of Management Messages
- Generating RSA Host and Server Keys for SSH Access
- SSH/SCP Integration with Radius Authentication
- SSH/SCP Integration with TACACS+ Authentication
- End User Access Control
- Ports and Trunking
- Port-Based Network Access Control
- VLANs
- Spanning Tree Protocol
- RSTP and MSTP
- Link Layer Discovery Protocol
- Quality of Service
- Accessing the Switch
- Part 2: IP Routing
- Basic IP Routing
- Routing Information Protocol
- IGMP
- OSPF
- OSPF Overview
- OSPF Implementation in BLADE OS
- OSPF Configuration Examples
- Remote Monitoring
- Part 3: High Availability Fundamentals
- High Availability
- Layer 2 Failover
- Server Link Failure Detection
- VRRP Overview
- Failover Methods
- BLADE OS Extensions to VRRP
- Virtual Router Deployment Considerations
- High Availability Configurations
- High Availability
- Part 4: Appendices
- Index
BLADE OS 5.1 Application Guide
BMD00113, September 2009 Chapter 12: OSPF 199
Interface Cost
The OSPF link-state algorithm (Dijkstra’s algorithm) places each routing device at the root of a tree
and determines the cumulative cost required to reach each destination. Usually, the cost is inversely
proportional to the bandwidth of the interface. Low cost indicates high bandwidth. You can
manually enter the cost for the output route with the following command:
Electing the Designated Router and Backup
In any area with more than two routing devices, a Designated Router (DR) is elected as the central
contact for database exchanges among neighbors, and a Backup Designated Router (BDR) is
elected in case the DR fails.
DR and BDR elections are made through the hello process. The election can be influenced by
assigning a priority value to the OSPF interfaces on the GbE2c. The command is as follows:
A priority value of 255 is the highest, and 1 is the lowest. A priority value of 0 specifies that the
interface cannot be used as a DR or BDR. In case of a tie, the routing device with the highest router
ID wins. Interfaces configured as passive do not participate in the DR or BDR election process:
Summarizing Routes
Route summarization condenses routing information. Without summarization, each routing device
in an OSPF network would retain a route to every subnet in the network. With summarization,
routing devices can reduce some sets of routes to a single advertisement, reducing both the load on
the routing device and the perceived complexity of the network. The importance of route
summarization increases with network size.
Summary routes can be defined for up to 16 IP address ranges using the following command:
where <range number> is a number 1 to 16, <IP address> is the base IP address for the range, and
<mask> is the IP address mask for the range. For a detailed configuration example, see
“Example 3: Summarizing Routes” on page 213.
>> # /cfg/l3/ospf/if <OSPF interface number>/cost <cost value (1-65535)>
>> #
/cfg/l3/ospf/if <OSPF interface number>/prio <priority value (0-255)>
>> # /cfg/l3/ospf/if <OSPF interface number>/passive enable
>> # /cfg/l3/ospf/range <range number>/addr <IP address>/mask <mask>