May 13, 2014
Two Citrix® NetScaler® VPX™ instances in AWS can be configured as a high availability (HA) pair. With one instance configured as the primary node and the other as the secondary node, the primary node accepts connections and manages servers while the secondary node monitors the primary. If, for any reason, the primary node is unable to accept connections, the secondary node takes over.
To deploy HA for VPX on AWS, you must configure at least two ENIs on the primary instance and a single ENI on the secondary instance. On each instance, configure the NetScaler IP (NSIP) address (the management address) on the default ENI. On the primary instance, use the additional ENIs for client and server connections.
For instructions on obtaining access and secret keys, in the AWS documentation, see "How Do I Get Security Credentials?" and "Creating, Modifying, and Viewing User Access Keys (AWS Management Console)." For instructions to create an IAM user and set permissions, see "Creating an IAM Account."
To deploy HA for two VPX instances on AWS, you must create the primary NetScaler VPX instances with three ENIs and the secondary NetScaler VPX with a single ENI.
Following is an example of launching a primary VPX instance with three ENIs:C:\aws-vpc-config>ec2-run-instances ami-bd2986d4 -n 1 -t m1.large -k keyPairName -f ./access-secret-key-file -a :0:subnet-15fa057e:"NSIP":10.20.15.21 -a :1:subnet-1547ba7e:"CLIENT-SIDE":10.20.10.21::::"10.20.10.22,10.20.10.23,10.20.10.24,10.20.10.25,10.20.10.26,10.20.10.27,10.20.10.28,10.20.10.29,10.20.10.30" -a :2:subnet-cc47baa7:"SERVER-SIDE":10.20.1.21::::"10.20.1.22,10.20.1.23,10.20.1.24,10.20.1.25,10.20.1.26,10.20.1.27,10.20.1.28,10.20.1.29,10.20.1.30"
Following is an example of launching a secondary VPX instance with a single ENI:C:\aws-vpc-config>ec2-run-instances ami-bd2986d4 -n 1 -t m1.large -k keyPairName -f access-secret-key-file -a :0:subnet-15fa057e:"NSIP":10.20.15.31
After the two NetScaler instances are UP, configure the HA pairing on both the instances. You have to configure the instance with two or more ENIs before configuring HA on the instance with one ENI. Use the add HA node command, from within the NetScaler CLI, or from the NetScaler GUI. For example:
On the VPX instance with two or more ENIs:
add HA node 1 10.20.15.31
On the VPX instance with one ENI:
add HA node 1 10.20.15.21
After you enter add HA node commands, the two nodes form an HA pair, and configuration information is synchronized between the two VPX instances.
For example, on the Secondary NetScaler VPX instance, at the NetScaler command line, type:
remove ha node
On the Primary NetScaler VPX instance, at the NetScaler command line, type:
remove ha node