Webmin installation on Centos

Installing the RPM

If you are using the RPM version of Webmin, first download the file from the downloads page, or run the command :

wget http://prdownloads.sourceforge.net/webadmin/webmin-1.870-1.noarch.rpm

then install optional dependencies with :

yum -y install perl perl-Net-SSLeay openssl perl-IO-Tty perl-Encode-Detect

and then run the command :

rpm -U webmin-1.870-1.noarch.rpm

Continue reading “Webmin installation on Centos” »

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CentOS 5 Repository fix using vault.centos.org

It’s a bit silly process, googled hours but found not solid way to update my old 32bit centos 5 linux box. So came up with a solution of my own. It might work for you, but no guarantee!

Step-1
Remove all .repo inside /etc/yum.conf.d/ directory

Step-2
Create a new repo file inside /etc/yum.conf.d/ 

nano /etc/yum.conf.d/CentOS-Vault.repo 

Update with the following section: Continue reading “CentOS 5 Repository fix using vault.centos.org” »

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Add Google Calendar to Thunderbird Mail Client

There are two plugins that must be installed:

Install both of these plugins, from within Thunderbird (Menu button | Plugins | See all and then search for Lightning and then Provider for Google. Click Add to Thunderbird and then, when prompted, restart the app).

Once these have been installed, and Thunderbird restarted, you’re ready to configure.

Adding a Google Calendar
Open up the Lightning calendar tab (click on the Lightning icon in the top right corner of the Thunderbird window). Right-click a blank spot in the Calendar pane (left side of the window) and click New Calendar. In the resulting window (Figure A), click On the Network and then click Next.

Created with GIMP

Figure A

Creating a new calendar in Lightning.
In the Locate your calendar window (Figure B), select Google Calendar, and click Next. Continue reading “Add Google Calendar to Thunderbird Mail Client” »

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Convert .ova and import it on Proxmox KVM virtualization

Let’s start uploading the exported ova file to the proxmox server. Extract the OVA file:

tar -xvf *.ova

This should output a couple of files from the OVA container, it should include an OVF file, which is the VM Defenition file, and a VMDK file, which is the actual hard disk image. Again, this may take a while.

Convert the vmdk to a Proxmox compatible qcow2 file:

qemu-img convert -f vmdk myvirtual-disk1.vmdk  -O qcow2 qcowdisk.qcow2

We now need to get the image into a VM with some hardware so that we can begin to use it. This is where things get tricky – the OVF file is not compatible with Proxmox and needs to be manually understood. The principle here is we are going to use the Proxmox web GUI to create a VM and replace the empty disk image which is created with our recently converted qcow2 image.

You can use vi to open the OVF file and understand some of the basic settings which are required for the VM. Open the OVF file and look for the following XML tags:

  • OperatingSystemSection
  • VirtualHardwareSection
  • Network
  • StorageControllers

Continue reading “Convert .ova and import it on Proxmox KVM virtualization” »

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Fix on connecting to NFS server from Proxmox Centos 7 Container

I hope you already know how to allow NFS from proxmox host server. if not, you may read my earlier post:

NFS fix on LXC Host Server

I was actually receiving a error like below:

# mount -t nfsd nfsd /proc/fs/nfsd
mount: nfsd is write-protected, mounting read-only
mount: cannot mount nfsd read-only

My proxmox edition was 5.0-30 and my CentOS was 7.

However, this is a bit different rather looking the other one as mentioned above. I was experiencing connecting my Centos 7 LXC container to a NFS server in the network. The regular tweak didn’t work. So, had to spend a while googling the solution. Found the correct one on a forum thread. But eventually it worked. For this you need to edit the file

nano /etc/pve/lxc/<your container ID>.conf

Add the below line in the conf file:

lxc.aa_profile: unconfined

Reboot the container. And now try to connect the NFS server. It should work.

 

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BIND ACL to restrict zone trasfer with IP address

You need to define ACL in /etc/named.conf or /etc/bind/named.conf.local file. Let us say IP 1.2.3.4 and 1.2.3.5 are allowed to transfer your zones.

# vi named.conf or vi /etc/bind/named.conf.local

Here is sample entry for domain domain.org.bd (ns1 configuration):

acl trusted-servers {
1.2.3.4; //ns1
1.2.3.5; //ns2
};

zone "domain.org.bd" {
 type master;
 file "/var/lib/bind/domain.org.bd.hosts";
 also-notify {
1.2.3.5; 
 };
 notify yes;
 allow-transfer { trusted-servers; };
 };

Continue reading “BIND ACL to restrict zone trasfer with IP address” »

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LEMP on Centos 6

In this guide, we’ll walk you through installing all of these components (except for Linux, which is already installed as your OS when you create the server).

Install the Extra Packages for Enterprise Linux Repository (or EPEL for short):sudo yum install epel-release
Run a yum update to sync your packages with the new EPEL repository:

sudo yum update

Install MySQL:

sudo yum install mysql-server

Activate MySQL:

sudo service mysqld start

Configure your MySQL installation:

sudo /usr/bin/mysql_secure_installation

Make it so that MySQL will start automatically on server reboot: Continue reading “LEMP on Centos 6” »

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Enable VNC viewer for Proxmox 2.x/3.x with tightvnc

Configure Proxmox host for TLS connections: This configures the host to accept VNC connections.

aptitude install openbsd-inetd

Run this to get your KVM id’s :

qm list
root@homenet-home10 /etc # qm list
VMID NAME STATUS MEM(MB) BOOTDISK(GB) PID 
101 freenas stopped 1024 32.00 0 
102 debpbx running 512 0.00 573304 
105 winxp stopped 512 15.01 0 
7012 ltsp-ldap-openfire-KVM running 512 9.00 495870 
7016 fbc16-kvm running 512 8.00 462697 
7159 win7 stopped 2048 0.00 0 
27014 ltsp-term-KVM stopped 512 0.00 0

edit /etc/inetd.conf , put a port for each kvm you want to access using kvm

#port kvm
59055 stream tcp nowait root /usr/sbin/qm qm vncproxy 105
59058 stream tcp nowait root /usr/sbin/qm qm vncproxy 7159

restart openbsd-inetd Continue reading “Enable VNC viewer for Proxmox 2.x/3.x with tightvnc” »

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Install Apache Tomcat 8.5 on CentOS 7.3

Prerequisites

Server with CentOS 7 – 64bit
2 GB or more RAM (Recommended)
Root Privileges on the server

Step 1 – Install Java (JRE and JDK)

In this step, we will install the Java JRE and JDK from the CentOS repository. We will install Java 1.8.11 on the server with the yum command.

Run this command to install Java JRE and JDK from CentOS repository with yum:

yum -y install java-1.8.0-openjdk.x86_64 java-1.8.0-openjdk-devel.x86_64

It will take some time, wait until the installation finished.

Then you should check the Java version with the command below:

java -version

You should see results similar to the ones below:

openjdk version "1.8.0_111"
OpenJDK Runtime Environment (build 1.8.0_111-b15)
OpenJDK 64-Bit Server VM (build 25.111-b15, mixed mode)

Step 2 – Configure the Java Home Environment Continue reading “Install Apache Tomcat 8.5 on CentOS 7.3” »

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Load Balancing using Ldirectord on Linux (Apache) web server

For this setup, we need four nodes (two Apache nodes and two load balancer nodes) and five IP addresses: one for each node and one virtual IP address that will be shared by the load balancer nodes and used for incoming HTTP requests.

I will use the following setup here:

Apache node 1: webserver1.tm.local (webserver1) – IP address: 192.168.0.103; Apache document root: /var/www
Apache node 2: webserver2.tm.local (webserver2) – IP address: 192.168.0.104; Apache document root: /var/www
Load Balancer node 1: loadb1.tm.local (loadb1) – IP address: 192.168.0.101
Load Balancer node 2: loadb2.tm.local (loadb2) – IP address: 192.168.0.102
Virtual IP Address: 192.168.0.105 (used for incoming requests)

In this tutorial I will use Ubuntu 8.04 LTS for all four nodes, just install basic Ubuntu 8.04 LTS on all four nodes. I want to say first that this is not the only way of setting up such a system. There are many ways of achieving this goal but this is the way I take. I do not issue any guarantee that this will work for you! I also recommend you to have a DNS server in place. Continue reading “Load Balancing using Ldirectord on Linux (Apache) web server” »

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