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Instead of configuring a virtual machine as a DHCP server, you can use the virtual DHCP server for your virtual network. To configure the virtual DHCP server: 1. Open the  Virtual Server Administration Website . 2. Under  Virtual Networks , select Configure  and then click the virtual network. 3. In  Virtual Network Properties , click  DHCP server . 4. Check the  Enabled  checkbox, then configure the necessary DHCP server options. 5. Click OK.

The Hot Standby Router Protocol, HSRP, provides a mechanism which is designed to support non-disruptive failover of IP traffic in certain circumstances. In particular, the protocol protects against the failure of the first hop router when the source host cannot learn the IP address of the first hop router dynamically. The protocol is designed for use over multi-access, multicast or broadcast capable LANs (e.g., Ethernet). HSRP is not intended as a replacement for existing dynamic router discovery mechanisms and those protocols should be used instead whenever possible. A large class of legacy host implementations that do not support dynamic discovery are capable of configuring a default router. HSRP provides failover services to those hosts. Using HSRP, a set of routers work in concert to present the illusion of a single virtual router to the hosts on the LAN. This set is known as an HSRP group or a standby group. A single router elected from the group is responsible for forwarding ...

What do you need to know about EIGRP? Before you configure EIGRP, there are some things you should know about it first. Here they are: EIGRP is the Enhanced Interior Gateway Routing Protocol. EIGRP is a Cisco proprietary routing protocol based on their original Interior Gateway Routing Protocol. EIGRP can only be used on networks where all routers are Cisco routers. The administrative distance for EIGRP is 90 and 170 for internal and external EIGRP, respectively. What features does EIGRP offer? Automatic redistribution of routes between IGRP and EIGRP. Ability to turn off and on EIGRP and IGRP on individual interfaces of the router. Fast network convergence thanks to EIGRP's DUAL algorithm (convergence is when all routers know about all the networks that every other router is offering). Incremental Updates that save network bandwidth and speed convergence. Reduced router CPU load, as compared to IGRP. EIGRP uses neighbor discovery to find and keep track of neighboring ...

Maybe you have a new router or you want to verify that you have security properly configured on your existing router. Either way, password security is critical to properly securing your Cisco router. So let’s get started configuring passwords on your Cisco router. Types of Cisco Router Passwords When it comes to basic password security, there are three basic types: Line Passwords Privileged mode Passwords (enable mode) Username Passwords (optional) Let’s explore these. Line Passwords Line passwords are configured on router lines. Examples of lines are: Console Line - The console is the main serial administrative port on a router. This is where you configure the router when it is new and has no network configuration. Aux Line – The aux line is an auxiliary port. Like the console, it is a physical port on every router. You can think of it as a backup console port. Besides being a backup console port, the aux port is periodically used for administrative console d...

Console ports are not Ethernet ports All too often, new Cisco admins confuse Cisco's console port to be an Ethernet port. However, the console port on Cisco routers and switches is a SERIAL port (not Ethernet). That means that it is designed to connect to the COM port (serial port) on your PC. Although the cable that connects to it has an RJ45 on the end, just like an Ethernet cable, an Ethernet cable will not work to connect these two together. What you need is a serial "rolled cable" if you are going to directly connect the router to the PC. What's a Terminal Server? A "terminal server" is also called an access server. This is a device that commonly provides access FROM dumb terminals TO the network. However, you can turn this around and also use it to allow a single device to allow access TO the device, FROM the network. The most well known Cisco access servers are the 2509 and 2511. While these are discontinued models, they are still used today at many ...

Traffic Policing and Shaping Configuration Both the Traffic policing and Class-based traffic shaping features are implemented using the MQC. The MQC is used to classify traffic by defining a traffic class, set traffic policy by defining a traffic policy (where policing and shaping is implemented) and is assigned to a specific interface. Setting Up Traffic Classification The first step involves traffic classification setup; traffic that is matched to a specific class can have a number of different actions taken against it. For the purposes of this article, the action to be taken will be to police or shape the matched traffic.  Setting Up a Traffic Policy The second step involves traffic policy setup; the traffic policy is where specific actions can be configured. As stated before, in the context of this article, this is where the traffic policing and shaping are configured. Setting Up Assignment of the Configured Traffic Policy onto a Specific Interface The third step in...

Introduction This guide is intended to provide you with simple instructions on how to install Nagios from source (code) on Ubuntu and have it monitoring your local machine inside of 20 minutes. No advanced installation options are discussed here - just the basics that will work for 95% of users who want to get started. These instructions were written based on an Ubuntu 6.10 (desktop) installation. They should work for an Ubuntu 7.10 install as well. What You'll End Up With If you follow these instructions, here's what you'll end up with: Nagios and the plugins will be installed underneath /usr/local/nagios Nagios will be configured to monitor a few aspects of your local system (CPU load, disk usage, etc.) The Nagios web interface will be accessible at http://localhost/nagios/ Required Packages Make sure you've installed the following packages on your Ubuntu installation before continuing. Apache 2 PHP GCC compiler and development libraries GD deve...

·          Generic Attribute Registration Protocol (GARP) VLAN Registration Protocol (GVRP) is an application defined in the IEEE 802.1Q standard that allows for the control of VLANs. ·          GVRP runs only on 802.1Q trunk links. ·          GVRP prunes trunk links so that only active VLANs will be sent across trunk connections. ·          GVRP expects to hear join messages from the switches before it will add a VLAN to the trunk. ·          GVRP updates and hold timers can be altered. ·          GVRP ports run in various modes to control how they will prune VLANs. ·          GVRP can be configured to dynamically add and manage VLANS to the VLAN database for trunking purposes. Configuring GVRP GVRP is suppo...

·          VLANs are local to each switch's database, and VLAN information is not passed between switches. ·          Trunk links provide VLAN identification for frames traveling between switches. ·          Cisco switches have two Ethernet trunking mechanisms: ISL and IEEE 802.1Q. ·          Certain types of switches can negotiate trunk links. ·          Trunks carry traffic from all VLANs to and from the switch by default but can be configured to carry only specified VLAN traffic. ·          Trunk links must be configured to allow trunking on each end of the link. Enabling Trunking Trunk links are required to pass VLAN information between switches. A port on a Cisco switch is either an access port or a trunk port. Access ports belong to a single VL...

·          VLANs are assigned to individual switch ports. ·          Ports can be statically assigned to a single VLAN or dynamically assigned to a single VLAN. ·          All ports are assigned to VLAN 1 by default ·          Ports are active only if they are assigned to VLANs that exist on the switch. ·          Static port assignments are performed by the administrator and do not change unless modified by the administrator, whether the VLAN exists on the switch or not. ·          Dynamic VLANs are assigned to a port based on the MAC address of the device plugged into a port. ·          Dynamic VLAN configuration requires a VLAN Membership Policy Server (VMPS) client, server, and database to operate properly...