Computer Network

How to Design Network Server

2007-07-27T15:26:00.000-07:00

Network server is a most important component of a computer network because the entire computer network is administered, controlled and managed through it. Before designing a network server for your organization, you should have the adequate knowledge about the following things.

Server Processor

Processor is a heart of the CPU. It processes all the commands, instructions and commands and execute them to perform certain actions. Pentium processors are very reliable in performance and speed and trend is growing to use the multiprocessor servers to share the load on each processor. If one processor fails to work due to any reason, there is no effect on the other processor in the same server so it’s a wise decision of the network administrators to use the multiprocessor server for company’s network.

Hard Disk

Hard disks are used to store all the data in permanently. Hard disk is a mechanical device and while selecting the hard disk you should consider the S.M.A.R.T (Smart Monitoring and Reporting Technology). This technology monitors the hard drives and predicts the any failure in the hard drivers. Today, most of the server providers provide hot swap disk drives, this means that if one there is any error occurred in the hard drives, it can be replaced with the other hard drives while the server is in the working mode.

Clustering

In a clustering environment, two or more servers operate as a single server and the failure of the one server does not affect on the other servers. Clustered environment has the benefits such as high performance, reliability and load balancing.

Memory Performance

While selecting the physical memory for the server it should be considered the memory support Error Correcting Code technology. ECC technology fixes and repairs any single bit errors and report the multi bit errors. High memory is very vital for the server for its best performance, speed and continuous work.

Power Supply

Most of the computers come with the multi power supplies. This means in case of failure of the one power supply, does not affect on the other power supply in the same computer and in this way computer works normally. Multi power supplies are hot swappable like the hard disks i.e. faulty power supplies can be replaced with the new ones while the server is in the working mode.

UPS

UPS or uninterrupted power supply are very important in a network environment because a sudden jerk of the electricity may cause of the hard drives or mother boards of the server as well as the other computers in the network. A UPS normally provide a backup of 3-4 hours and during that time server and other computers can be setup and the files or other data can be saved.

Cooling Fans

The cooling system inside the server is provided by the cooling fans. Cooling fans pull the cool air inside the server and through out the heat from the server. The failure of the cooling fan results in the automatic shutdown of the server due to the high buildup of the heat. Many vendors of the computer systems are providing the hot swappable cooling fans.

Computer Monitoring Hardware

There is a specially designed adapter to monitor the performance of the different parts of the hardware of the computer. This adapter can also be controlled by a modem remotely.

Computer Monitoring Software

Different computer monitoring software is available in the market and their main purpose is to monitor the performance of the server and the client computers.

Data Server Location

Network server should be placed in a dust free, cooling capable and clean environment and only the authorized users should be allowed to enter in the server room.

Starting a Router

2007-07-15T05:09:00.000-07:00

Enhanced Editing Commands

Router>Shape the future of internetworking by creating unpreced

Shape the future of internetworking by creating unprecedented value for customers, employees, and partners.

Router Command History

Ctrl-P or Up Arrow = Recalls last (previous) commands

Ctrl-N or Down Arrow = Recalls more recent commands

show history= Shows command buffer contents

history size line = Sets the buffer size permanently

terminal history size lines = Sets session command buffer size

show version Command

wg_ro_a#show version
Cisco Internetwork Operating System Software
IOS (tm) 2500 Software (C2500-JS-L), Version 12.0(3), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-1999 by cisco Systems, Inc.
Compiled Mon 08-Feb-99 18:18 by phanguye
Image text-base: 0x03050C84, data-base: 0x00001000
ROM: System Bootstrap, Version 11.0(10c), SOFTWARE
BOOTFLASH: 3000 Bootstrap Software (IGS-BOOT-R), Version 11.0(10c), RELEASE SOFTWARE(fc1)
wg_ro_a uptime is 20 minutes
System restarted by reload
System image file is "flash:c2500-js-l_120-3.bin"
(output omitted)
--More--
Configuration register is 0x2102

Viewing the Configuration

show running-config and show startup-config Commands

In RAM

wg_ro_c#show running-config
Building configuration...

Current configuration:

!version 12.0
!
-- More --

In NVRAM

wg_ro_c#show startup-config
Using 1359 out of 32762 bytes
!
version 12.0
!
-- More --

•Displays the current and saved configuration

Summary

•The startup of a Cisco router requires that you verify the physical installation, power up the router, and view the Cisco IOS software output on the console.
•The router startup sequence is similar to the startup sequence of the Catalyst switch. The router first performs POST, then it finds and loads the IOS image. Finally, it finds and loads the device configuration file.
•Use the enable command to access the privileged EXEC mode from the user EXEC mode.

Summary (Cont.)

•The Cisco router uses Cisco IOS software with extensive command-line input help facilities, including context-sensitive help.
•The Cisco IOS CLI includes an enhanced editing mode that provides a set of editing key functions.
•The Cisco router CLI provides a history or record of commands you have entered. This feature, called the command history, is particularly useful to help you recall long or complex commands or entries.
•After logging in to a Cisco router, you can verify the router initial startup status using the router status commands: show version, show running-configuration, and show startup-configuration.

Port LEDs During Switch POST

2007-07-15T04:09:00.002-07:00

1. At the start, all port LEDs are green.
2. Each LED turns off after its test completes.
3. If a test fails, its LED turns amber.
4. System LED turns amber if any test fails.
5. If no test fails, POST completes.
6. On POST completion, LEDs blink, then turn off.

Initial Bootup Output from the Catalyst 1900 Switch

Initial Bootup Output from the Catalyst 2950 Switch

--- System Configuration Dialog ---

At any point you may enter a question mark '?' for help.
Use ctrl-c to abort configuration dialog at any prompt.
Default settings are in square brackets '[ ]'.
Continue with configuration dialog? [yes/no]: yes
Enter IP address: ip_address
Enter IP netmask: ip_netmask
Would you like to enter a default gateway address? [yes]: yes
IP address of the default gateway: ip_address
Enter a host name: host_name
Enter enable secret: secret_password
Would you like to configure a Telnet password? [yes] yes
Enter Telnet password: telnet_password
Would you like to enable as a cluster command switch? no
Enter cluster name: cls_name

Logging In to the Switch and Entering the Enable Password

> (User-Mode Prompt)

> enable

Enter password:

# (Privileged-Mode Prompt)

# disable

Switch Command-Line Help Facilities

Context-Sensitive Help

- Provides a list of commands and the arguments associated with a specific command

Console Error Messages

- Identifies problems with any switch commands that are incorrectly entered so that you can alter or correct them

Command History Buffer

- Allows recall of long or complex commands or entries for reentry, review, or correction

Configuring the Switch

Configuration Modes:
•Global configuration mode
–wg_sw_a#configure terminal
–wg_sw_a(config)#
•Interface configuration mode
–wg_sw_a(config)#interface e0/1
–wg_sw_a(config-if)#

Configuring Switch Identification

Switch Name

(config)#hostname wg_sw_c

wg_sw_c(config)#

•Sets the local identity for the switch

Configuring the Switch IP Address

wg_sw_a(config)#ip address {ip address} {mask}

Example:

wg_sw_a(config)#ip address 10.5.5.11 255.255.255.0

Configuring the Switch Default Gateway

wg_sw_a(config)#ip default-gateway {ip address}

Example:

wg_sw_a(config)#ip default-gateway 172.20.137.1

Showing Switch Initial Startup Status

wg_sw_a#show version

•Displays the configuration of the system hardware, software version, names and sources of configuration files, and boot images

wg_sw_a#show running-configuration

*Displays the switch’s current active configuration file

wg_sw_a#show interfaces

*Displays statistics for all interfaces configured on the switch

wg_sw_a#show ip

•Displays the IP address, subnet mask, and default gateway

Switch show version Command

wg_sw_a#show version
Cisco Catalyst 1900/2820 Enterprise Edition Software
Version V8.01.01 written from 171.068.229.225
Copyright (c) Cisco Systems, Inc. 1993-2001
wg_sw_c uptime is 15day(s) 21hour(s) 53minute(s) 11second(s)
cisco Catalyst 1900 (486sxl) processor with 2048K/1024K bytes of memory
Hardware board revision is 5
Upgrade Status: No upgrade currently in progress.
Config File Status: No configuration upload/download is in progress
27 Fixed Ethernet/IEEE 802.3 interface(s)
Base Ethernet Address: 00-50-BD-73-E2-C0

Switch show interfaces Command

wg_sw_a#show interfaces ethernet 0/1
Ethernet 0/1 is Enabled
Hardware is Built-in 10Base-T
Address is 0050.BD73.E2C1
MTU 1500 bytes, BW 10000 Kbits
802.1d STP State: Forwarding Forward Transitions: 1
Port monitoring: Disabled
Unknown unicast flooding: Enabled
Unregistered multicast flooding: Enabled
Description:
Duplex setting: Half duplex
Back pressure: Disabled
--More--

Showing the Switch IP Address

wg_sw_c#show ip
IP Address: 10.5.5.11
Subnet Mask: 255.255.255.0
Default Gateway: 10.5.5.3
Management VLAN: 1
Domain name:
Name server 1: 0.0.0.0
Name server 2: 0.0.0.0
HTTP server : Enabled
HTTP port : 80
RIP : Enabled
wg_sw_a#

Summary

•The startup of a Catalyst switch requires that you verify the physical installation, power up the switch, and view the Cisco IOS software output on the console.
•The Catalyst switches have several status LEDs that are generally lit in green when the switch is functioning normally but turn amber when there is a malfunction.
•The Catalyst POST is executed only when the switch is powered up. The POST uses the switch port LEDs to indicate test progress and status.
•During initial startup, if POST test failures are detected, they are reported to the console. If POST completes successfully, you can configure the switch.

Summary (Cont.)

•When you start any mode on a Catalyst switch, begin in user EXEC mode. To change modes, you must enter a password.
•The Catalyst switch uses Cisco IOS software with several command-line input help facilities, including context-sensitive help.
•The Catalyst switch IOS software has the global configuration mode and the interface configuration mode.
•After logging in to a Catalyst switch, you can verify the switch initial startup status using the switch status commands: show version, show running-configuration, and show interfaces.

Starting a Switch

2007-07-15T03:41:00.001-07:00

Catalyst 2950 Switch LED Indicators

Catalyst 1900 Switch LED Indicators

Initial Startup of the Catalyst Switch

•System startup routines initiate switch software.
•Initial startup uses default configuration parameters.

Before you start the switch,verify the cabling and console connection.

Attach the power cable plug to the switch power supply socket.

Observe the boot sequence:

- LEDs on the switch chassis

- Cisco IOS software output text

An Overview of Cisco Device Startup

2007-07-15T03:31:00.000-07:00

External Configuration Sources

*Configurations can come from many sources.
•Configurations will act in device memory.

Cisco IOS User Interface Functions

•A CLI is used to enter commands.
•Operations vary on different internetworking devices.
•Users type or paste entries in the console command modes.
•Enter key instructs device to parse and execute the command.
•Two primary EXEC modes are user mode and privileged mode. •Command modes have distinctive prompts.

Cisco IOS Software EXEC Mode

•There are two main EXEC modes for entering commands.

Cisco IOS Software EXEC Mode (Cont.)

Summary

•The Cisco IOS software platform is implemented on all Cisco hardware platforms.
•You will use Cisco IOS software to communicate the configuration details that implement the learning objectives of this course.
•You can configure a switch or router from sources that are external to the device.
•Cisco IOS software uses a CLI as its traditional console environment. While Cisco IOS software is a core technology, Cisco IOS software operation details vary on different internetworking devices.
•The Cisco IOS software supports two EXEC command modes: user and privileged.

Course Introduction

2007-07-15T03:08:00.001-07:00

Course Objectives

Upon completing this course, you will be able to:
•Execute an add, move, or change so that the network functions in accordance with the new requirement, given a new network requirement
•Use available configuration tools to establish connectivity to the appropriate network device to complete the initial device configuration
•Build a functional configuration to support the specified network operational requirements, given a network design
•Use the command-line interface to accurately determine network device operational status and network performance

Course Objectives (Cont.)

Upon completing this course, you will be able to:
•Manage operating system image files to maintain an accessible operating system file and according to best practices, given a network topology
•Use IOS commands to manage device configuration files to reduce device downtime according to best practices
•Use the appropriate show commands to display network operational parameters so that anomalies are detected
•Use the appropriate debug commands to monitor network operational parameters so that events and anomalies are detected

Communications and Services Certifications

Cisco Icons and Symbols

Operating Cisco IOS Software

Objectives

Upon completing this lesson, you will be able to:
•Set up console connections between Cisco network devices and a terminal, given a need to configure and monitor network equipment
•Describe the features of the Cisco IOS user interface
•Identify the differences between the user EXEC and privileged EXEC modes

Configuring Network Devices

•Configuration sets up the device with the following:
– Network policy of the functions required
– Protocol addressing and parameter settings
– Options for administration and management
•Catalyst switch memory has initial configuration with default settings
•Cisco router will prompt for initial configuration if there is no configuration in memory

Certified Of Network

2007-07-15T02:47:00.000-07:00

CCNA Information

Cisco Certified Network Associate

The CCNA Course consists of sections 1 through 4 of the Academy program. It is equivalent to 280 hours of instruction to provide students with a basic foundation in networking. Students who successfully complete this portion of the program are eligible to earn Cisco Certified Network Associate (CCNA™) certification.

The test now has router configuration questions which are NOT multiple-choice. Commands to answer this type of question must be typed in correctly. Therefore, hands-on skills are more important than ever. TVCC provides students with the time and equipment needed to be proficient at configuring Cisco equipment, as well as providing CCNA certified instructors who have a working knowledge of local area networks.

The CCNA certification indicates a foundation in and an apprentice knowledge of networking for the small office/home office (SOHO) market.

CCNA certified associates can install, configure, and operate LAN, WAN, and dial access services for small networks (100 nodes or fewer), including but not limited to use of these protocols: IP, IGRP, IPX, Appletalk, Frame Relay, IP RIP, VLANs, RIP, Ethernet, Access Lists.