Failback

failback

#!/usr/bin/env bash

# Usage
if [ -z "$4" ] || [ "$1" == "--help" ]
then
  echo "Please specify host (the system coming back), failover host (where the failover container"
  echo "lives), the failover container, and the drbd resource"
  echo "  failover server-b server-a server-b-fo r1"
  exit
fi

host="$1"
failover="$2"
container="$3"
resource="$4"

# unmount the resource on the contianer
if ! ssh root@"$container" /usr/local/sbin/failback
then
  echo "Failover on $container failed"
  exit 1
fi

# set the resource as secondary
if ! ssh root@"$failover" /sbin/drbdadm secondary $resource 2>/dev/null
then
  echo "Set resource $resource to secondary failed on $failover"
  exit 1
fi

# verify that resource is connected
if ! ssh root@"$host" /sbin/drbdadm cstate "$resource" 2>/dev/null | grep "^Connected$" > /dev/null
then
  echo "Resource $resource is not connected on $host"
  exit 1
fi

# verify that resource is uptodate
if ! ssh root@"$host" /sbin/drbdadm dstate "$resource" 2>/dev/null | grep "^UpToDate/UpToDate$" > /dev/null
then
  echo "Resource $resource is not up to date"
  exit 1
fi

# verify the resource is secondary everywhere
if ! ssh root@"$host" /sbin/drbdadm role "$resource" 2>/dev/null | grep "^Secondary/Secondary$" > /dev/null
then
  echo "Resource $resource is not secondary everywhere"
  exit 1
fi

# promote the resource on the host
if ! ssh "$host" /usr/local/sbin/drbd-autopromote "$resource" /mnt/btrfs
then
  echo "Failed to promote $resource on $host"
  exit 1
fi

# try to start/restart services on the container, reload haproxy config
ssh root@"$host" service haproxy start
ssh root@"$host" service haproxy reload
ssh root@"$host" service keepalived restart