- What are the
prerequisites for setting up AutoScale?
prerequisites for setting up AutoScale, see
- Can the
CloudPlatform AutoScale feature be used without a NetScaler appliance?
- No. The
NetScaler appliance is currently required for the AutoScale feature to work. If
the CloudPlatform administrator configures AutoScale in a network that does not
include a NetScaler appliance, CloudPlatform throws an error.
- What happens
if the AutoScale feature is used with a NetScaler release that does not support
- If the
AutoScale feature is used with a NetScaler release that does not support
AutoScale, the CloudPlatform user interface throws an error. CloudPlatform also
writes a message to the log file, indicating that the configured NetScaler does
not support AutoScale.
versions of CloudPlatform and NetScaler should I use to implement AutoScale?
information about NetScaler releases that support AutoScale, see
- In a load
balancing rule, can manually provisioned virtual machine instances coexist with
instances provisioned by the AutoScale feature?
- No. The
CloudPlatform virtual machine group in a load balancing rule can contain only
manually provisioned instances or only instances provisioned by the AutoScale
feature. They cannot coexist.
- Is there a
limit on the number of virtual machine instances to which we can scale up by
- Yes. The
CloudPlatform administrator specifies the maximum number of members to which
the configuration can scale up. When the limit is reached, virtual machines are
not provisioned even if the scale-up condition is satisfied. The upper limit
prevents uncontrolled spawning of VMs due to misconfiguration of the AutoScale
feature or unexpected load conditions.
AutoScale events observable?
- The events
generated for deploying or destroying virtual machines are observable. These
events are logged in the NetScaler logs (ns.log) and in the CloudPlatform logs
(management-server.log). However, you cannot observe the metric values
collected by NetScaler monitors.
- What metrics
can be used in AutoScale policies?
- In an
AutoScale policy, you can use any metric that is exposed through SNMP, or any
NetScaler statistics associated with the load balancing virtual server used in
the AutoScale configuration. For example, you can use metrics associated with
CPU, memory, or disk usage, and NetScaler metrics such as throughput or
- What should
a CloudPlatform administrator do before performing maintenance tasks on a
CloudPlatform network in which AutoScale is configured?
CloudPlatform administrator should disable the AutoScale configuration from the
CloudPlatform user interface. Disabling the AutoScale configuration temporarily
disables any scale-up or scale-down events. However, disabling AutoScale for an
application, in CloudPlatform, does not affect the ability of the NetScaler
appliance to serve traffic to existing virtual machines.
AutoScale configured, are any configured VM limits enforced on the user
NetScaler appliance works in the context of an AutoScale user account.
Therefore, any limits that the CloudPlatform administrator has imposed on the
number of VMs that can be created by the account are automatically enforced
when the NetScaler appliance attempts to create more VMs than are permitted.
- Is AutoScale
supported in a high availability (HA) NetScaler pair?
Currently, HA mode is not supported for AutoScale.