Why Bother Mounting an ISO Image?
Sometimes you find yourself in a situation where you need to take an ISO image and utilize it like a CD or DVD. The popularity of virtual machines and the ability to manipulate larger files over high speed Internet increase the chances that you’ll have to work with an ISO image from time to time. Being able to mount an ISO image as though it were an inserted CD/DVD can make manipulating these kinds of files a bit easier– especially if your computer doesn’t have a CD/DVD ROM drive installed.
Let’s say you have a third party program you need to install, but the vendor only gives you an ISO file. Let’s say the name of the file is thirdparty.iso and you have downloaded that file to /export/home/myhome. Here’s an easy way to utilize this file under Solaris: Continue reading How to Mount and ISO Image in Solaris and Linux
From the Service Provider’s Perspective
In part one of this topic, we discussed how to manage a sub-delegation for reverse DNS records once your ISP provides this service for you. Here in part two, we’ll discuss how to provide the sub-delegation of a reverse DNS range to another user. So in this situation, think of yourself as the provider offering the service for a customer or end user.
What You’ll Need
After you have received the request from the customer, you will need to confirm that they have created the proper zone for the Continue reading How to Sub-Delegate Reverse DNS Records Part 2
The Purpose of DNS Sub-Delegation
Let’s say you have acquired a static IP range from your ISP. Now that you have that range, you decide you also want to control the
PTR records for these addresses as well. But,
PTR records typically belong to the ISP. However, you do not want to depend on the ISP for each change you’d like to make; you want more control. How can your gain more control over those
The way to gain this control is through DNS Sub-Delegation. DNS Sub-Delegation is when your ISP forwards
PTR requests to your name server so that you can have control over your record updates. In other words, the ISP delegates their authority over their
PTR records to your DNS server.
If you understood the implications of that last sentence, you’ll realize that you will need your own local DNS service that controls your domain. After all, if you don’t control your own domain, how are you going to control the
PTR records once they are delegated to you? In this post, we’ll assume that you will manage your
PTR records with your own DNS server. Continue reading How to Sub-Delegate Reverse DNS Records Part 1
Why bother with tftp?
Many network devices such as Cisco routers and switches use
tftp in order to download their IOS config updates.
tftp can also be used for network based installs or for booting up diskless systems. Knowing how to setup a
tftp server comes in quite handy when circumstances like these arise.
Getting started . . .
The Network Topology
Let’s say we’re dealing with a private network– 192.168.100.0/24. We’ll designate our
tftp server and
tftp test client as 192.168.100.5 and 192.168.100.105 respectively. You will need
superuser privileges on both your server and client in order to successfully perform all of these commands.
Get the Necessary Packages
Log on to 192.168.100.5 and download the necessary programs; make sure they survive reboots:
# yum install tftp-server xinetd
# chkconfig tftp on Continue reading How to Setup a TFTP Server Under CentOS/RHEL 6