6.0 Base Lining:Baselining is the process of measuring network parameters such as network traffic, error packets, overall usage etc. Establishing a baseline when the network is performing normally enables to troubleshoot any problems introduced at a later stage. Baselining also enables network managers to plan the network expansion based on the current trend. Network monitors are useful establishing a baseline.
7.0 Cisco Network Management Tools:
Important Cisco network management tools that you need to know
1. Cisco Works (includes CiscoView)
5. WAN Manager
Note that, CiscoView is bundled with CiscoWorks. CiscoView is also available as a standalone product.
CiscoWorks: CiscoWorks is an important network management product from Cisco. It provides graphical view of Cisco device panel displays, allowing easy fault recognition and diagnosis. CiscoWorks uses SNMP (Simple Network Management Protocol) for monitoring and control of SNMP capable devices on a network. One of the big advantages of CiscoWorks is that it can be seamlessly integrated with third party SNMP network management platforms such as HP OpenView.
CiscoWorks is available in four versions:
1. CiscoWorks Blue - suitable for integrated IBM SNA and IP environments.
2. CiscoWorks Windows - A PC-based network configuration and
troubleshooting tools. Suitable for small to medium size networks.
3. CiscoWorks Switched Internetwork Solutions (CWSI) - Suitable for campus LAN management. Include VlanDirector, TrafficDirector, and CiscoView.
4. CiscoWorks2000 - A web based network management suite.
Note that CWSI contains TrafficDirector application as an integral part.
Netsys: Netsys is a suite of simulation based design and troubleshooting tools. These tools allow designers to plan the network and see the network behavior before committing the designs or changes to the actual network.
TrafficDirector: By using TrafficDirector in conjunction with the embedded RMON agents allow us to measure traffic utilization, error rates, and other statistical parameters on any selected port(s).
VlanDirector: VlanDirector is a Cisco VLAN management tool. Given below are salient characteristics:
1. Graphical interface
2. Drag and drop functionality for assigning users to VLANs
3. Enables configuration, management, and monitoring of Cisco switches and routers.
4. VlanDirector can be integrated with common SNP management platforms.
WAN Manager: WAN Manager provides easy configuration, management, fault detection of wide-area multiservice networks.]
The following are some important terms with respect to buffers:
1. Hits: This is the count of successful attempts to allocate a buffer when required.
2. Misses: This is the count of buffer allocation attempts that resulted in increasing the buffer pool for allocating a buffer.
3. Trims: This is the count of buffers released to the system because they were not being used.
4. Created: This is the count of new buffers created in response to misses. Note that this field is displayed only for dynamic buffer pools, not for static buffer pools (ex. interface buffer pools).
5. Failures: This is the total number of allocation requests that have failed because no buffer was available. This will result in loss of datagram.
Runts: This is the number of packets that have been discarded
because they are smaller than the medium's minimum packet size.
For Ethernet, a packet size of less than 64 bytes is considered
In the given example, there are 342 runts per 133+ million bytes. This is more than one runt per million bytes, which is acceptable. Therefore, it is likely that the network is experiencing excessive collisions.
Giants: This is the number of packets that have been discarded because they exceeded the maximum allowable size of the medium. For Ethernet, a packet size of more than 1518 bytes is considered a giant.
10.0 Some important Cisco IOS show commands:
The command 'show cdp neighbors' displays information about the
Cisco devices directly connected to the router.
The command 'show cdp neighbors detail' provides additional information including network-layer protocol information.
The command 'cdp run' enables CDP. Note that CDP is enabled by default. To disable CDP, use the command 'no cdp run' in the global configuration mode.
The command 'show ip route' displays the entries in the routing
table. The routes are displayed by a preceding protocol keyword.
Some of the protocol keywords are:
I -IGRP; E - EGP ; B - BGP ; O - OSPF ; I - IGRP; R - RIP
The network address of the remote network, the address of the next router to the remote network, and the interface through which the remote network can be reached are provided for each route in the output. This command is widely used for diagnostic purposes for troubleshooting the routing table entries.