Usage

Usage

Keepalived is a routing software written in C. The main goal of this project is to provide simple and robust facilities for loadbalancing and high-availability to Linux system and Linux based infrastructures. Loadbalancing framework relies on well-known and widely used Linux Virtual Server (IPVS) kernel module providing Layer4 loadbalancing. Keepalived implements a set of checkers to dynamically and adaptively maintain and manage loadbalanced server pool according their health. On the other hand high-availability is achieved by VRRP protocol. VRRP is a fundamental brick for router failover. In addition, Keepalived implements a set of hooks to the VRRP finite state machine providing low-level and high-speed protocol interactions. Keepalived frameworks can be used independently or all together to provide resilient infrastructures.

Sample pillar

Simple virtual IP on an interface:

keepalived:
  cluster:
    enabled: True
    instance:
      VIP1:
        nopreempt: True
        priority: 100 (highest priority must be on primary server, different for cluster members)
        virtual_router_id: 51
        auth_type: AH
        password: pass
        address: 192.168.10.1
        interface: eth0
      VIP2:
        nopreempt: True
        priority: 150 (highest priority must be on primary server, different for cluster members)
        virtual_router_id: 52
        auth_type: PASS
        password: pass
        address: 10.0.0.5
        interface: eth1

Multiple virtual IPs on single interface:

keepalived:
  cluster:
    enabled: True
    instance:
      VIP1:
        nopreempt: True
        priority: 100 (highest priority must be on primary server, different for cluster members)
        virtual_router_id: 51
        password: pass
        addresses:
        - 192.168.10.1
        - 192.168.10.2
        interface: eth0

Use unicast:

keepalived:
  cluster:
    enabled: True
    instance:
      VIP1:
        nopreempt: True
        priority: 100 (highest priority must be on primary server, different for cluster members)
        virtual_router_id: 51
        password: pass
        address: 192.168.10.1
        interface: eth0
        unicast_src_ip: 172.16.10.1
        unicast_peer:
          172.16.10.2
          172.16.10.3

Disable nopreempt mode to have Master. Highest priority is taken in all cases:

keepalived:
  cluster:
    enabled: True
    instance:
      VIP1:
        nopreempt: False
        priority: 100 (highest priority must be on primary server, different for cluster members)
        virtual_router_id: 51
        password: pass
        addresses:
        - 192.168.10.1
        - 192.168.10.2
        interface: eth0

Notify action in keepalived:

keepalived:
  cluster:
    enabled: True
    instance:
      VIP1:
        nopreempt: True
        notify_action:
          master:
            - /usr/bin/docker start jenkins
            - /usr/bin/docker start gerrit
          backup:
            - /usr/bin/docker stop jenkins
            - /usr/bin/docker stop gerrit
          fault:
            - /usr/bin/docker stop jenkins
            - /usr/bin/docker stop gerrit
        priority: 100 # highest priority must be on primary server, different for cluster members
        virtual_router_id: 51
        password: pass
        addresses:
        - 192.168.10.1
        - 192.168.10.2
        interface: eth0

Track/vrrp scripts for keepalived instance:

keepalived:
  cluster:
    enabled: True
    instance:
      VIP2:
        priority: 100
        virtual_router_id: 10
        password: pass
        addresses:
        - 192.168.11.1
        - 192.168.11.2
        interface: eth0
        track_script: check_haproxy
      VIP3:
        priority: 100
        virtual_router_id: 11
        password: pass
        addresses:
        - 192.168.10.1
        - 192.168.10.2
        interface: eth0
        track_script:
          check_random_exit:
            interval: 10
          check_port:
            weight: 50
    vrrp_scripts:
      check_haproxy:
        name: check_pidof
        args:
          - haproxy
      check_mysql_port:
        name: check_port
        args:
          - 3306
          - TCP
          - 4
      check_ssh:
        name: check_port
        args: "22"
      check_mysql_cluster:
        args:
          # github: olafz/percona-clustercheck
          # <user> <pass> <available_when_donor=0|1> <log_file> <available_when_readonly=0|1> <defaults_extra_file>
          - clustercheck
          - clustercheck
          - available_when_donor=0
          - available_when_readonly=0
      check_random_exit:
        interval: 10
        timeout: 5
        content: |
          #!/bin/bash
          exit $(($RANDOM%2))
        weight: 50

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