To configure snmp client version 3 on a Red Hat server you will need to install the packages net-snmp-utils and net-snmp. yum install net-snmp-utils net-snmp Make sure the snmpd service is stopped before you can configure it. service snmpd stop Create a new SNMPv3 user called “andrew”. The authentication password is “auth-pass” using MD5...
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Software
Configuring SNMPv3 client on Red Hat Linux
Add new disk to Red Hat Linux server, create new filesystem without reboot.
If you are running a VMware virtual Red Hat Linux server then it is very easy to add a new disk. For physical servers with hot add capability this is also possible. I am going to show you how to add a new disk to Red Hat Linux complete with a new filesystem, without...
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Expanding VMware virtual IDE disk for Windows XP
In VMware ESX 4.x the default disk type for Windows XP 32bit virtual machine is IDE. If you did not size your drive correctly, you will be unable to expand this virtual disk later using the VMware management client. But if you had selected SCSI adapter instead of IDE, then expanding the disk after...
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Script to power down many Windows servers
If you ever have the need to power down hundreds of Windows servers, then here is a script to do just that. This script will work for Windows 2000, 2003 and 2008. The servers will shut down gracefully. for /F %%a in (names.txt) do call:Sub %%a goto:eof :Sub echo Shutting Down %1 #shutdown -m...
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Configure the DVD or Linux ISO as software repository for Red Hat Enterprise Linux
You downloaded and installed Red Hat Enterprise Linux on your server becasue you just want to test it out. During installation you selected base server, after installation you realize that you need to install additional packages. But since you did not purchase the Red Hat license it is not possible to install additional packages...
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SSH Login without password using public key authentiation
On Computer A Create the public and private keys using the command ssh-keygen # ssh-keygen -t rsa Generating public/private rsa key pair. Enter file in which to save the key (/root/.ssh/id_rsa): Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /root/.ssh/id_rsa. Your public key has been...
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How to extend the filesystem on a Vmware ESX guest Red Hat Linux server
Being the administrator of a large Linux shop, I have had to extend the filesystems on the Red Hat Linux server a few times. Each time I had the opportunity to extend the filesystem, I found that I struggled to remember the commands and steps. This is because Linx is a very command line...
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Unable to login to remote server via ssh
A funny thing happened to one of my Red Hat 5 Enterprise servers after applying the errata. I rebooted the servers as usual after applying the updates, and they came up just fine. But unfortunately I was not able to logon remotely via ssh to a server. I tried various different accounts including root,...
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How to create a new superuser in Linux
The administrative account ‘root’ is the most powerful user in Linux and Unix. This account is created by default during installation of the operating system. Most security consultants will recommend that the root account be deleted or renamed. This is to make it harder for a hacker to find out what a valid user...
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Troubleshoot problem with yum update and rebuild the rpm database
I have created a step by step approach to troubleshoot a problem with performing yum update and how to rebuild the rpm database. I received and error while trying to update the Redhat Enterprise 5 server kernel using yum update. Looking at the output of yum update it seems that the dependency mkinitrd was...
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