Building a High Availability Cluster with HAProxy and Keepalived
Setting up a highly available load balancing cluster requires two primary components: HAProxy for traffic distribution and Keepalived for failover management. This setup uses two virtual machines running CentOS 7.Environment PreparationInstall the EPEL repository and required packages on both nodes:yum install -y epel-release
yum install -y hap ...
Posted on Sat, 27 Jun 2026 16:14:40 +0000 by xenoalien
Linux Infrastructure Architecture Overview for Small-Medium Websites
Components of a Small-Medium Scale Website Architecture
Customers/Users
Visitors accessing the website
Security Guard - Firewall (firewalld)
Implements access control policies
Receptionist - Load Balancer (nginx)
Schedules and distributes incoming user requests
Waiter - Web Server (nginx)
Processes user requests
Chef - Database Server ...
Posted on Wed, 24 Jun 2026 16:36:56 +0000 by nmohamm
Keepalived VIP Loss Due to systemd-networkd Restart
In a test environment using Ubuntu 18.04 with Keepalived v1.3.9 (installed via apt-get) in a Master-Backup configuration alongside Nginx, an unexpected loss of the Virtual IP (VIP) on the Master node was observed. The service became unreachable, yet no failover occurred—both nodes showed no Keepalived transition logs.
Restarting Keepalived on t ...
Posted on Sun, 21 Jun 2026 17:06:19 +0000 by mlla2
High-Availability MySQL Dual-Master Replication with Keepalived
This guide outlines the implementation of a highly available MySQL dual-master replication cluster protected by Keepalived for automatic VIP failover. The setup ensures continuous database service despite node failures.
Prerequisites
Two Linux servers: 192.168.199.49 (Node A) and 192.168.199.50 (Node B)
Shared virtual IP (VIP): 192.168.199.52
...
Posted on Sat, 20 Jun 2026 16:44:53 +0000 by thefollower
Configuring Keepalived for High Availability Load Balancing
Starting the Service and Enabling Auto-Start
On lb01:
[root@lb01 nginx]# systemctl start keepalived.service
[root@lb01 nginx]# systemctl enable keepalived.service
On lb02:
[root@lb02 ~]# systemctl start keepalived.service
[root@lb02 ~]# systemctl enable keepalived.service
Packet Capture Analysis with Wireshark
Once the service is running, cap ...
Posted on Sat, 13 Jun 2026 17:03:11 +0000 by mbuckley2000
Deploying Nginx High Availability with Keepalived on Huawei Cloud
Keepalived Fundamentals
Keepalived is an open-source software solution designed to monitor server health and manage failover scenarios. When a web node encounters downtime or errors, Keepalived automatically removes the affected node from the cluster and redistributes traffic to healthy servers. Once repairs are completed, the original node rej ...
Posted on Sat, 06 Jun 2026 17:23:54 +0000 by axman505
Heartbeat-driven Apache HA Setup and Production Maintenance Guide
Practical Example: Highly Available Apache Web Service with Heartbeat
1. Lab Environment
Two RHEL/CentOS hosts:
node-a – 192.168.1.130
node-b – 192.168.1.129
A floating virtual IP (VIP) 192.168.1.131/24 will be managed by Heartbeat and bound to whichever node is active.
2. Install Apache on Both Nodes
sudo yum install -y httpd
3. Prepare the ...
Posted on Sun, 17 May 2026 16:29:21 +0000 by saqibb
Keepalived High Availability Configuration and Testing
Virtual IP Configuration
virtual_ipaddress {
10.0.0.3/24 dev eth0 label eth0:1
}
track_script {
health_check
}
Failover Testing
[root@lb01 ~]# systemctl is-active nginx
active
[root@lb01 ~]# ip a | grep 0.3
inet 10.0.0.3/24 scope global secondary eth0:1
[root@lb01 ~]# systemctl stop nginx
[root@lb01 ~]# ip a | grep 0.3
# VIP migrated after ...
Posted on Sat, 16 May 2026 22:21:57 +0000 by BrianG