VLANs and Firewalls
At AppNexus every customer has a private VLAN, or Virtual Local Area Network, in each datacenter where they operate equipmentreserve servers. Your VLAN is a list of sequential of IP addresses to be assigned to the instances you launch on in the AppNexus systemenvironment. Your VLAN can consist of 8, 24, 56 or 120 , ..., (2^N-8) IP addresses; eight addresses in each range are reserved for networking equipment so that equipment will it can behave as though it was part of your indiviudal individual VLAN.
- You can assign specific IP addresses to your equipment by using the optional "
--ip" parameter for the
manage-instance launchcommand. If no specific IP is selected, the next available IP in the range will be automatically assigned. For more information, see manage-instance.
- Instance IPs are static; if the server reboots or the instance goes offline, the IP will remain the same.
VLANs provide security by segregating each customer's traffic from AppNexus and other customers' traffic and also by regulating traffic from the Internet via according to a customer-controlled Access Control List (ACL). You can view your current ACLs in the customer portal at https://portal.appnexus.com/networking.php?index=acl.
- By default all inbound traffic from the Internet to your IP block is denied except for ping (ICMP Echo---used to verify that the host is up). Customers With your ACL, you can explicitly permit TCP/, UDP/, or ANY traffic for particular source and destination IPs and ports, request ALLOW or DENY rule. Default rule is deny all explicitly permitted traffic is allowed to pass.Initial access rules are configured based on the customer questionnaire.
- You will be assigned a separate VLAN in each datacenter where you have equipment. By default, all ports between your two VLANs in different datacenters will be open. Traffic between LAX1 and NYM1 travels over the Internet and is not encrypted.
- All outgoing traffic is allowed.
- You'll set your inital ACL via the customer questionnaire, and you can change it at any time. At the moment, ACL changes must go through Support. Please see How to Request Set Firewall ChangesRules for more information. Soon there will be an API for ACLs and you will also be able to use the customer portal.
- All traffic within a VLAN is allowed so all instances can freely communicate with each other.
- All outgoing traffic from your VLAN is allowed.
- By default, all ports/traffic between same-customer VLANs in different datacenters is open. (Note that traffic between LAX1 and NYM1 travels over the Internet and is not encrypted.)
If you run out of IP addresses in your VLAN
If you outgrow a VLAN, we can AppNexus will assign you a new, larger one. This can take up to one workday , and you as support staff configures the ACL for the new VLAN. You will then have need to migrate instances from the old VLAN to the new one. This can be done without downtime; you will assign each item in your VLAN a second IP address for the duration of the migration. You will get detailed instructions how to migration from one VLAN to another Detailed instructions on VLAN migration will be provided when you make your request to Support.
1. When you launch new instance, please use "
--ip" flag of "
manage-instance launch" command to explicitly declare IP address of instance in new address block. - Really it'll be part of instruction - Vladimir
Meanwhile I'll prepare instructions on how to deal with multi-VLAN environment, how to migrate instances from old IP space to the new one with the existing API/CLI functionality, et cetera. - Actually Alexander Novitskiy is communicating with GiftReal (RT:5483) and OpenAds (RT:5118) on this.
Assigning IP addresses from your VLAN
manage-instance launch --name, --cpu-units, --server-id, --memory, --disk, --share-name,
--path, --ip, --upload, --authorized-keys, --async
Note: We assume that customer IP requests are for usable IP addresses; the eight addresses used for network gear have already been accounted for when an IP range is allocated.
As always, please create a ticket at https://portal.appnexus.com/ or contact us at firstname.lastname@example.org if you have any questions or concerns.