High Availability: Linux Clustering di RHEL6/CentOS6 dengan Luci dan Ricci

On this occasion, the Techsoftcenter web will share a little about “Clusters” where according to the title above is “High Availability: Linux Clustering on RHEL6 / CentOS6 with Luci and Ricci”. as we know that to do clustering can use several methods but for the opportunity this time we learn a little “High Availability – Linux Clustering using Luci and Ricci on OS Linux RHEL6 / CentOS6” To equalize perception, this time topology information uses Host Server: IP 192.168,100,250, has several VMs as follows:
arrif-base: IP 192.168,100,120 (arrif-base)
arrif-vm1: IP (node1)
arrif-vm1: IP (node2)
IP: (virtual IP that is automatically formed by Ricci on the active node)
Where for the storage media to use the hard drive, if you don’t have a storage media, you can start creating an iSCSI target / multipath initiator on RHEL6 / CentOS6 Linux first on the article link.
First, do / configure / etc / hosts or you can use DNS server, configuration / etc / hosts

Insert the following file on all three VM servers:

Provide/customize hostname naming on both nodes and servers:

Disable SELinux

On both nodes install the following packets:

Install HA Management on only one node, this example is installed on arrif-vm1 (node1)

Iptables / firewall settings for using High Availability Cluster on RHEL / CentOS Allow access to cman (Cluster Manager):

Setting firewall dlm (Distributed Lock Manager):

Setting firewall mod_cluster (Conga remote agent):

Setting firewall Luci (Conga User Interface server):

Setting firewall igmp (Internet Group Management Protocol):

Save the iptables / firewall configuration

After completing the firewall configuration, set the password to clear on both nodes

Run the service cluster automatically when both boot nodes:

Run the web management service automatically when booting (the node that is made as web management):

https: // arrif-vm1: 8084
1. Add nodes to both service clusters

Homabase ==> Manage Cluster
klik “Create”
Cluster Name: cluster-name
Use the Same Password for All Nodes: yes
Node Name:
Download Packages: yes
Reboot Nodes Before Joining Cluster: yes
Enable Shared Storage Support: yes

2. In the Resources Tab

Tambah/add service “Resources” IP Address
Klik “Resources” => Add => IP Address
IP Address:
Netmask: 24

3. Add/add resource filesystem

Name: webroot
Filesystem Type: ext4
Mount Point    : /var/www/html
Device, FS Label, or UUID: /dev/mapper/1IET_00010001p1

4. Tambah Resource http scripts

Add : Scipt
Name: httpd
Full Path to Script File: /etc/init.d/httpd

Next in the “Failover Domain” configuration stage
Click add to add failover

Name: failover-domain
Prioritized: yes
Restricted: yes
set member cluster dan prioritinya

Next, configure “Fence Device”
Because it uses KVM virtualization, use fencing Fence Virt (Multicast Mode) to be able to kill/take over service nodes from a cluster.

Next, configure “Fence Device” which will be used on the service nodes.

On the “Nodes” tab click to add a fence device
Click “Add Fence Method”
Method Name: “FenceMethod”
after forming “FenceMethod” click “Add Fence Instance” and select KVM-Fencing xvm Virtual Machine Fencing

To be able to use fencing in KVM, there are several packages that must be installed “fence-virtd-multicast” on the host computer, so that they can parse the vhost / node in it.

so it becomes as follows:

Create configure fence_virtd on the host computer:

Run the fence_virtd service and set it up to run when running OS

copy fence certificate file that is on the host computer to each node

Now we will add a “Service Groups” with the name apache-webservice

Service Name : apache-webserver
Automatically Start This Service : yes
Run Exclusive: yes
Failover Domain : failover-domain
Recovery Policy : Relocate

For other configurations leave the default, and sort by the following steps for adding “Add Resource” to “Service Groups” apache-webserver:

– IP address =
– webroot = ext4 / /dev/mapper/1IET_00010001p1 mount to /var/www/html
– httpd = script /etc/init.d/httpd