gcaa-patroni.txt

sed -i 's/enforcing/disabled/g' /etc/selinux/config /etc/selinux/config
sed -i "\$ a $1 192.168.8.73\t\t$NEW_HOST auhsmaxdbp01\t$NEW_HOST" /etc/hosts
sed -i "\$ a $1 192.168.8.74\t\t$NEW_HOST auhsmaxdbp02\t$NEW_HOST" /etc/hosts
sed -i "\$ a $1 192.168.8.76\t\t$NEW_HOST auhsmaxdbp03\t$NEW_HOST" /etc/hosts
systemctl disable firewalld

vgcreate vg00 /dev/sdb
lvcreate -l 100%FREE -n lv00 vg00
mkfs.xfs /dev/vg00/lv00


dnf -y install epel-release
dnf -y update
dnf -y install yum-utils
dnf -y install https://download.postgresql.org/pub/repos/yum/reporpms/EL-8-x86_64/pgdg-redhat-repo-latest.noarch.rpm
dnf -qy module disable postgresql
dnf -y install postgresql12-server postgresql12 postgresql12-devel
ln -s /usr/pgsql-12/bin/* /usr/sbin/
curl -O https://ftp.postgresql.org/pub/repos/yum/common/pgdg-rhel8-extras/redhat/rhel-8.5-x86_64/etcd-3.5.5-1.rhel8.x86_64.rpm
dnf -y install etcd-3.5.5-1.rhel8.x86_64.rpm


vi /etc/watchdog.conf
watchdog-device = /dev/watchdog
mknod /dev/watchdog c 10 130
modprobe softdog
chown postgres /dev/watchdog

mv /etc/etcd/etcd.conf /etc/etcd/etcd.conf.ori

cat - <<HEREDOC >/etc/etcd/etcd.conf
ETCD_NAME=auhsmaxdbp01
ETCD_DATA_DIR="/var/lib/etcd/auhsmaxdbp01"
ETCD_LISTEN_PEER_URLS="http://192.168.8.73:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.8.73:2380"
ETCD_INITIAL_CLUSTER="auhsmaxdbp01=http://192.168.8.73:2380,auhsmaxdbp02=http://192.168.8.74:2380,auhsmaxdbp03=http://192.168.8.76:2380"
ETCD_INITIAL_CLUSTER_STATE="new"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_ADVERTISE_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_ENABLE_V2="true"
HEREDOC

cat - <<HEREDOC >/etc/etcd/etcd.conf
ETCD_NAME=auhsmaxdbp02
ETCD_DATA_DIR="/var/lib/etcd/auhsmaxdbp02"
ETCD_LISTEN_PEER_URLS="http://192.168.8.74:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.8.74:2380"
ETCD_INITIAL_CLUSTER="auhsmaxdbp01=http://192.168.8.73:2380,auhsmaxdbp02=http://192.168.8.74:2380,auhsmaxdbp03=http://192.168.8.76:2380"
ETCD_INITIAL_CLUSTER_STATE="new"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_ADVERTISE_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_ENABLE_V2="true"
HEREDOC

cat - <<HEREDOC >/etc/etcd/etcd.conf
ETCD_NAME=auhsmaxdbp03
ETCD_DATA_DIR="/var/lib/etcd/auhsmaxdbp03"
ETCD_LISTEN_PEER_URLS="http://192.168.8.76:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.8.76:2380"
ETCD_INITIAL_CLUSTER="auhsmaxdbp01=http://192.168.8.73:2380,auhsmaxdbp02=http://192.168.8.74:2380,auhsmaxdbp03=http://192.168.8.76:2380"
ETCD_INITIAL_CLUSTER_STATE="new"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_ADVERTISE_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_ENABLE_V2="true"
HEREDOC

vi .bash_profile
export PGDATA="/var/lib/pgsql/12/data"
export ETCDCTL_API="3"
export PATRONI_ETCD_URL="http://127.0.0.1:2379"
export PATRONI_SCOPE="pg_cluster"
patroni1=192.168.8.73
patroni2=192.168.8.74
patroni3=192.168.8.76
ENDPOINTS=$auhsmaxdbp01:2379,$auhsmaxdbp02:2379,$auhsmaxdbp03:2379

systemctl start etcd && systemctl enable etcd && systemctl status etcd

etcdctl endpoint status --write-out=table --endpoints=$ENDPOINTS

dnf -y install python3 python3-devel python3-pip gcc libpq-devel
pip3 install psycopg2
pip3 install --upgrade testresources
pip3 install --upgrade setuptools
pip3 install psycopg2
dnf -y install python3-etcd
dnf -y install patroni patroni-etcd watchdog

mkdir -p /etc/patroni
cat - <<HEREDOC >/etc/patroni/patroni.yml
scope: pg_cluster
namespace: /service/
name: auhsmaxdbp01

restapi:
    listen: 192.168.8.73:8008
    connect_address: 192.168.8.73:8008

etcd:
    hosts: 192.168.8.73:2379, 192.168.8.74:2379, 192.168.8.76:2379

bootstrap:
  dcs:
    ttl: 30
    loop_wait: 10
    retry_timeout: 10
    maximum_lag_on_failover: 1048576
    postgresql:
      use_pg_rewind: true
      use_slots: true
      parameters:

  initdb:
  - encoding: UTF8
  - data-checksums

  pg_hba:
  - host replication replicator 127.0.0.1/32 md5
  - host replication replicator 192.168.8.73/0 md5
  - host replication replicator 192.168.8.74/0 md5
  - host replication replicator 192.168.8.76/0 md5
  - host all all 0.0.0.0/0 md5

  users:
    admin:
      password: admin
      options:
        - createrole
        - createdb

postgresql:
  listen: 192.168.8.73:5432
  connect_address: 192.168.8.73:5432
  data_dir: /var/lib/pgsql/12/data
  bin_dir: /usr/pgsql-12/bin
  pgpass: /tmp/pgpass
  authentication:
    replication:
      username: replicator
      password: replicator
    superuser:
      username: postgres
      password: postgres

watchdog:
  mode: required
  device: /dev/watchdog
  safety_margin: 5

tags:
    nofailover: false
    noloadbalance: false
    clonefrom: false
    nosync: false
HEREDOC

mkdir -p /etc/patroni
cat - <<HEREDOC >/etc/patroni/patroni.yml
scope: pg_cluster
namespace: /service/
name: auhsmaxdbp02

restapi:
    listen: 192.168.8.74:8008
    connect_address: 192.168.8.74:8008

etcd:
    hosts: 192.168.8.73:2379, 192.168.8.74:2379, 192.168.8.76:2379

bootstrap:
  dcs:
    ttl: 30
    loop_wait: 10
    retry_timeout: 10
    maximum_lag_on_failover: 1048576
    postgresql:
      use_pg_rewind: true
      use_slots: true
      parameters:

  initdb:
  - encoding: UTF8
  - data-checksums

  pg_hba:
  - host replication replicator 127.0.0.1/32 md5
  - host replication replicator 192.168.8.73/0 md5
  - host replication replicator 192.168.8.74/0 md5
  - host replication replicator 192.168.8.76/0 md5
  - host all all 0.0.0.0/0 md5

  users:
    admin:
      password: admin
      options:
        - createrole
        - createdb

postgresql:
  listen: 192.168.8.74:5432
  connect_address: 192.168.8.74:5432
  data_dir: /var/lib/pgsql/12/data
  bin_dir: /usr/pgsql-12/bin
  pgpass: /tmp/pgpass
  authentication:
    replication:
      username: replicator
      password: replicator
    superuser:
      username: postgres
      password: postgres

watchdog:
  mode: required
  device: /dev/watchdog
  safety_margin: 5

tags:
    nofailover: false
    noloadbalance: false
    clonefrom: false
    nosync: false
HEREDOC

mkdir -p /etc/patroni
cat - <<HEREDOC >/etc/patroni/patroni.yml
scope: pg_cluster
namespace: /service/
name: auhsmaxdbp03

restapi:
    listen: 192.168.8.76:8008
    connect_address: 192.168.8.76:8008

etcd:
    hosts: 192.168.8.73:2379, 192.168.8.74:2379, 192.168.8.76:2379

bootstrap:
  dcs:
    ttl: 30
    loop_wait: 10
    retry_timeout: 10
    maximum_lag_on_failover: 1048576
    postgresql:
      use_pg_rewind: true
      use_slots: true
      parameters:

  initdb:
  - encoding: UTF8
  - data-checksums

  pg_hba:
  - host replication replicator 127.0.0.1/32 md5
  - host replication replicator 192.168.8.73/0 md5
  - host replication replicator 192.168.8.74/0 md5
  - host replication replicator 192.168.8.76/0 md5
  - host all all 0.0.0.0/0 md5

  users:
    admin:
      password: admin
      options:
        - createrole
        - createdb

postgresql:
  listen: 192.168.8.76:5432
  connect_address: 192.168.8.76:5432
  data_dir: /var/lib/pgsql/12/data
  bin_dir: /usr/pgsql-12/bin
  pgpass: /tmp/pgpass
  authentication:
    replication:
      username: replicator
      password: replicator
    superuser:
      username: postgres
      password: postgres

watchdog:
  mode: required
  device: /dev/watchdog
  safety_margin: 5

tags:
    nofailover: false
    noloadbalance: false
    clonefrom: false
    nosync: false
HEREDOC


systemctl start patroni && systemctl enable patroni && systemctl status patroni

dnf -y install haproxy
mv /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg.orig
cat - <<HEREDOC >/etc/haproxy/haproxy.cfg
global
    log         127.0.0.1 local2
    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     1000
    user        haproxy
    group       haproxy
    daemon
    stats socket /var/lib/haproxy/stats

defaults
    mode                    tcp
    log                     global
    option                  tcplog
    retries                 3
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout check           10s
    maxconn                 900

listen stats
    mode http
    bind *:7000
    stats enable
    stats uri /

listen primary
    bind 192.168.10.76:5000
    option httpchk OPTIONS /master
    http-check expect status 200
    default-server inter 3s fall 3 rise 2 on-marked-down shutdown-sessions
    server patroni1 192.168.8.73:5432 maxconn 100 check port 8008
    server patroni2 192.168.8.74:5432 maxconn 100 check port 8008
    server patroni3 192.168.8.76:5432 maxconn 100 check port 8008

listen standby
    bind 192.168.8,76:5001
    balance roundrobin
    option httpchk OPTIONS /replica
    http-check expect status 200
    default-server inter 3s fall 3 rise 2 on-marked-down shutdown-sessions
    server patroni1 192.168.8.73:5432 maxconn 100 check port 8008
    server patroni2 192.168.8.74:5432 maxconn 100 check port 8008
    server patroni3 192.168.8.76:5432 maxconn 100 check port 8008
HEREDOC

 systemctl start haproxy &&  systemctl enable haproxy
 
 All 3 node following steps

dnf -y install keepalived

vi /etc/sysctl.conf
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1

sysctl --system
sysctl -p


mv /etc/keepalived/keepalived.conf  /etc/keepalived/keepalived.conf.ori

ip addr show enp0s3

cat - <<HEREDOC >/etc/keepalived/keepalived.conf 
vrrp_script chk_haproxy {
        script "pkill -0 haproxy"
        interval 5
        weight -4
        fall 2
        rise 1
}

vrrp_script chk_lb {
        script "pkill -0 keepalived"
        interval 1
        weight 6
        fall 2
        rise 1
}

vrrp_script chk_servers {
        script "echo 'GET /are-you-ok' | nc 127.0.0.1 7000 | grep -q '200 OK'"
        interval 2
        weight 2
        fall 2
        rise 2
}

vrrp_instance vrrp_1 {
        interface enp0s3
        state BACKUP
        virtual_router_id 51
        priority 99
        virtual_ipaddress_excluded {
                192.168.8.75
        }
        track_interface {
                enp0s3 weight -2
        }
        track_script {
                chk_haproxy
                chk_lb
        }
}
HEREDOC

Kindly ask end cus for IP Address for virtual and check the ethernet card name as well.

Before starting keepalived find out who is leader in pgsql cluster.
#patronictl -c /etc/patroni/patroni.yml list

On leader node run below command

systemctl start keepalived
systemctl status keepalived
systemctl enable keepalived

Other 2 node run above command 
----------------
dnf update -y
curl -o /etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release https://www.redhat.com/security/data/fd431d51.txt
curl --create-dirs -o /etc/rhsm/ca/redhat-uep.pem https://ftp.redhat.com/redhat/convert2rhel/redhat-uep.pem
curl -o /etc/yum.repos.d/convert2rhel.repo https://ftp.redhat.com/redhat/convert2rhel/8/convert2rhel.repo
dnf clean all
dnf -y install convert2rhel
convert2rhel --username rajatjpatel@gmail.com --password 

convert2rhel --username=rajatjpatel@gmail.com --auto-attach