Veritas InfoScale™ 8.0.2 Solutions in Cloud Environments

Failover across AWS subnets using overlay IP - Linux

InfoScale clusters let you fail over IPs - and thereby, the application configured for HA - between different subnets in the same AZ or in different AZs.

AWS does not allow the private IP of one subnet to be failed over to a different subnet. To overcome this limitation, InfoScale Enterprise provides an overlay IP, which is defined at the VPC level, so that it can be used across subnets.

The following graphic depicts a sample failover configuration across subnets within the same AZ using an overlay IP:

The following snippet is a service group configuration from a sample VCS configuration file (main.cf):

group appnetworkSG (
 	SystemList = { ip-172-34-20-109 = 0, ip-172-34-30-231 = 1 }
	 AutoStartList = { ip-172-34-20-109, ip-172-34-30-231 }
	 )

 	AWSIP AwsIp_Res (
	  	OverlayIP = "172.35.1.3/32"
  		Device = eth0
  		AWSBinDir = "/usr/local/bin"
		  )

 	IP Ip_Res (
	  	Device = eth0
  		Address = "172.35.1.3"
		  NetMask = "255.255.255.255"
  		)

 	NIC Nic_Res (
	  	Device = eth0
  		)

AwsIp_Res requires Ip_Res
Ip_Res requires Nic_Res

The following graphic depicts a sample failover configuration across subnets in different AZs using an overlay IP:

The following snippet is a service group configuration from a sample VCS configuration file (main.cf):

group appnetworkSG (
 	SystemList = { ip-172-34-20-109 = 0, ip-172-34-30-231 = 1 }
	 AutoStartList = { ip-172-34-20-109, ip-172-34-30-231 }
 	)

	 AWSIP AwsIp_Res (
		  OverlayIP = "172.35.1.3/32"
  		Device = eth0
  		AWSBinDir = "/usr/local/bin"
  		)

 	IP Ip_Res (
	  	Device = eth0
  		Address = "172.35.1.3"
  		NetMask = "255.255.255.255"
  		)

 	NIC Nic_Res (
  		Device = eth0
		  )

AwsIp_Res requires Ip_Res
Ip_Res requires Nic_Res