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The DHCP Relay Agent allows you to place DHCP clients and DHCP servers on different networks. Deploying DHCP in a single segment network is easy. All DHCP messages are IP broadcast messages, and therefore all the computers on the segment can listen and respond to these broadcasts. A single scope on a solitary DHCP server is all that is required. DHCP Messages on a Multisegment Network Things get a little more complicated when you have more than one subnet on your network. This is because the DHCP broadcast messages do not, by default, cross the router interfaces. There are several ways you can handle this situation. One alternative is to put a DHCP server on each segment. If you have just a few segments, you might consider this option. However, when you have a large organization, placing a DHCP server on each segment can increase cost and add to administrative effort. Relay To The Rescue A better option is to use fewer DHCP servers and place these machines in central locations. To sol

What is an Inventory?   An Inventory is the process of mounting media in the drive and reading the media label, which is then displayed in the  Devices  view. If this is the first time that Backup Exec (tm) has encountered this media, the media label is also added to the  Media  view.     Note : Each time new tape is introduced in the tape drive or robotic library, it must be inventoried so that the Backup Exec database gets updated with the new tape Information.     To Inventory a Tape/Robotic Library:   1. Insert the tape   2. Click the  Devices  tab   3. Select the correct tape drive/robotic library slot   4. Right-click on the tape drive/robotic library slot and select  Inventory  (Figure 1)   Figure 1   The inventory will complete and should display the correct tape name.   What is a Catalog?     When cataloging a tape, Backup Exec reads the header information from the tape and stores it in a file on the hard drive.   The information contained in the catalog i

You can add virtual disk units dynamically to a Linux® logical partition that uses IBM® i resources. This allows you to increase the storage capacity of your AIX® logical partition when needed. Virtual disks simplify hardware configuration on the server because they do not require you to add additional physical devices to the server in order to run Linux. You can allocate up to 64 virtual disks to a Linux logical partition. Each virtual disk supports up to 1000 GB of storage. Each virtual disk appears to Linux as one actual disk unit. However, the associated space in the i integrated file system is distributed across the disks that belong to the i logical partition. Distributing storage across the disks provides the benefits of device parity protection through i. Therefore, you do not have to use additional processing resources and memory resources by setting up device parity protection through Linux. IBM i provides the ability to dynamically add virtual disks to a Linux lo

An Overview of Repository Based Installation Linux distributions are essentially a collection of many different software packages combined with a Linux kernel. These packages are stored in repositories which may be accessed online to install and update Linux distributions. The key tools for performing these tasks on systems such as Red Hat Linux, Fedora and CentOS are called yum and rpm. Other Linux distributions (such as Debianand Ubuntu) use a different package management system which will be covered in Building a Debian or Ubuntu Xen Guest Root Filesystem using debootstrap. In terms of creating a Xen guest domain the yum and rpm tools can be used to install the base root filesystem on a blank disk image or partition by downloading the necessary packages from an online repository. This contrasts with the approach described in previous chapters whereby the root filesystem is simply copied from the host operating system Preparing to Create a Xen Guest Root Filesystem from R

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

Microsoft Windows 1. If needed, add new drives to the storage system. 2. If needed, create a hot spare using Navisphere Manager. 3. If needed, create an additional RAID group on the drives using Navisphere Manager. 4. Create (bind) additional LUNs on the RAID group using Navisphere Manager. 5. Assign the new LUNs to the server using Navisphere Manager. 6. Verify that the new LUNs were assigned to the server using Navisphere Manager. 7. On the server, verify that the server has access to the LUNs: a. On the Windows desktop, right-click My Computer and click Manage. b. In the left pane of the Computer Management dialog box, double-click on the storage icon. c. Click Disk Management. d. Verify that the LUNs that you added are listed in the right pane. 8. Start or restart the Navisphere Host Agent to push the server’s LUN mapping and operating system information to the storage system. 9. On the server, start PowerPath and verify that PowerPath s

Hyper-V Live Migration Configuration Requirements Before a running virtual machine can be migrated from one host to another there are some mandatory requirements that must first be met: Hyper-V 2008 R2 must be deployed on both hosts. The first version of Hyper-V does not support live migration. Source and destination Hyper-V hosts must be configured as a Failover cluster with shared storage enabled. Source and destination systems must be using shared storage (i.e. via SAN or iSCSI configurations) Source and destination systems must be running processors from the same manufacturer. It is not, for example, possible to migrate a virtual machine from an Intel based host to one containing an AMD CPU. The virtual machine on which the migration is to be performed must be configured as Highly Available and to use Cluster Shared Volumes. The virtual machine's Automatic Start Action setting must be set to do Nothing. All Hyper-V hosts in the Failover cluster must be configured t

Description of problem: Client is attempting to kickstart RHEL5 to a blade system with SAN attached storage. The customer is hitting an issue where anaconda complains with the following message at the beginning of the install: On virt console 1: Warning: /dev/sda is a read-only filesystem and hit OK to continue On virt console 3: parted exception: Warning: Unable to open /dev/sda read-write (Read-only file system). /dev/sda has been opened read-only The customer has to hit OK to accept this and the installation will then complete successfully. There are currently two LUNs presented from the SAN to the host. /dev/sda is indeed read-only and apparently it is a gatekeeper type device that is exported/presented to numerous hosts hence why it's read-only. /dev/sdb is the second LUN device that we want to install to. I've tried using the following entries in the kickstart file: ignoredisk --drives=sda clearpart --all --drives=sdb partition /boot --fstyp