Elastic IPs in Basic Zone

- Elastic IPs in Basic Zone - Similar to the public IP address, Elastic IP addresses are mapped to their associated - private IP addresses by using StaticNAT. The EIP service is equipped with StaticNAT (1:1) - service in an EIP-enabled basic zone. The default network offering, - DefaultSharedNetscalerEIPandELBNetworkOffering, provides your network with EIP and ELB network - services if a NetScaler device is deployed in your zone. Consider the following illustration - for more details. - - - - - - eip-ns-basiczone.png: Elastic IP in a NetScaler-enabled Basic Zone. - - - In the illustration, a NetScaler appliance is the default entry or exit point for the - &PRODUCT; instances, and firewall is the default entry or exit point for the rest of the data - center. Netscaler provides LB services and staticNAT service to the guest networks. The guest - traffic in the pods and the Management Server are on different subnets / VLANs. The - policy-based routing in the data center core switch sends the public traffic through the - NetScaler, whereas the rest of the data center goes through the firewall. - The EIP work flow is as follows: - - - When a user VM is deployed, a public IP is automatically acquired from the pool of - public IPs configured in the zone. This IP is owned by the VM's account. - - - Each VM will have its own private IP. When the user VM starts, Static NAT is - provisioned on the NetScaler device by using the Inbound Network Address Translation - (INAT) and Reverse NAT (RNAT) rules between the public IP and the private IP. - - Inbound NAT (INAT) is a type of NAT supported by NetScaler, in which the destination - IP address is replaced in the packets from the public network, such as the Internet, - with the private IP address of a VM in the private network. Reverse NAT (RNAT) is a type - of NAT supported by NetScaler, in which the source IP address is replaced in the packets - generated by a VM in the private network with the public IP address. - - - - This default public IP will be released in two cases: - - - When the VM is stopped. When the VM starts, it again receives a new public IP, not - necessarily the same one allocated initially, from the pool of Public IPs. - - - The user acquires a public IP (Elastic IP). This public IP is associated with the - account, but will not be mapped to any private IP. However, the user can enable Static - NAT to associate this IP to the private IP of a VM in the account. The Static NAT rule - for the public IP can be disabled at any time. When Static NAT is disabled, a new - public IP is allocated from the pool, which is not necessarily be the same one - allocated initially. - - - - - For the deployments where public IPs are limited resources, you have the flexibility to - choose not to allocate a public IP by default. You can use the Associate Public IP option to - turn on or off the automatic public IP assignment in the EIP-enabled Basic zones. If you turn - off the automatic public IP assignment while creating a network offering, only a private IP is - assigned to a VM when the VM is deployed with that network offering. Later, the user can - acquire an IP for the VM and enable static NAT. - For more information on the Associate Public IP option, see . - For more information on the Associate Public IP option, see the - Administration Guide. - - The Associate Public IP feature is designed only for use with user VMs. The System VMs - continue to get both public IP and private by default, irrespective of the network offering - configuration. - - New deployments which use the default shared network offering with EIP and ELB services to - create a shared network in the Basic zone will continue allocating public IPs to each user - VM. -