• Network Management
  • OSI and Network Management
  • SNMP and CMIP
  • MIB Structure
  • SNMP Protocol
  • SNMP Configuration
  • RMON
  • Syslog

Network Management

OSI and Network Management

There are 4 parts to the OSI management model:

• Orginizational – describes components of network management and their relationships
• Information – structure and storage of information, representation of objects
• Communication – method for data transfer between the agent and manager
• Functional – Fault, Configuration, Accounting, Performance, Security (FCAPS)

SNMP and CMIP

Simple Network Management Protocol (SNMP):

• made up of a protocol, a database structure, and a set of data objects
• SNMP v2c was released in ‘93, SNMP v3 is current
• TCP/IP adopted SNMP as a protocol in 1989

Common Management Information Protocol (CMIP):

• ISO standard
• made up of a complex set of standards

MIB structure

MIB I includes 114 objects, and the newer MIB II is expanded, with 185 objects defined.

There are objects administered by the Internet Activities Board (IAB), which are standardized. Vendors may also create custom objects, while it is recommended that they release the definitions of their objects, they are not always.

SNMP Protocol

There are three main functions that can be used by the Network Management Station, GetRequest, GetNextRequest, and SetRequest. SNMP v2c added a Bulk function to these, allowing more than one value to be requested at a time.

SNMP Configuration

Basic SNMP Configuration
Router(config) snmp-server community [string (acts as password)] [ro (read only) | rw (read/write)]

Specify the location and main contact of managed device
Router(config) snmp-server location [text]
Router(config) snmp-server contact [text]

RMON

• is an MIB
• based on IETF RFCs
• gets statistics by analyzing all frames on a segment
• RMON1 works on the data link layer
• RMON2 works on the network layer
• has a different group for each type of information it analyzes

Syslog

• based on UNIX syslog utility
• has 8 severity levels, from 0 (most critical) to 7 (least critical):
  • 0 – Emergencies
  • 1 – Alerts
  • 2 – Critical
  • 3 – Errors
  • 4 – Warnings
  • 5 – Notifications
  • 6 – Informational (default on Cisco IOS)
  • 7 – Debugging

Configuration:

Enable logging to all supported destinations:
Router(config)#logging on

Send log messages to a syslog server host:
Router(config)#logging [hostname | ip address]

Set logging severity level
Router(config)#logging trap [level name]

Include timestamp with syslog message:
Router(config)#service timestamps log datetime