---
title: "Limitations of vNIOS for AWS"
canonical: "https://docs.infoblox.com/space/NAIG/1487634463/Limitations%20of%20vNIOS%20for%20AWS"
format: markdown
---
Consider the limitations listed in this topic when deploying vNIOS for AWS.

# Common Limitations

- vNIOS for AWS instances do not support LAN2 interfaces.  
If you have configured the LAN2 interface on an instance, it might still function as expected. However, LAN2 interfaces are not supported because Infoblox has not qualified LAN2 on public cloud instances.  
Additionally, as NIOS supports high availability configurations from version 9.0.4, it treats the third interface as HA by default. Therefore, if you have configured a LAN2 interface, NIOS will treat it as an HA interface, causing errors and unexpected behavior.
- vNIOS for AWS does not discover a network resource if its name exceeds 63 characters in length. Ensure that the name of every AWS resource that must be discovered by NIOS does not exceed 63 characters.
- vNIOS for AWS instances running on NIOS 8.6.3 or the later versions of 8.6.x, deployed with R4 or R6i instance types, do not support downgrading NIOS to a version prior to 8.6.3 or setting up automatic synchronization of DNS data.
- Avoid interchanging network interfaces on a vNIOS instance as it can result in unexpected behavior.
- vNIOS for AWS does not support the use of Weighted Random Early Detection (WRED) mechanism in network schedulers because the Elastic Network Adapter (ENA) poll-mode driver does not provide the API required for 100 Gbps ENA interfaces and also because the ixgbevf driver for the Intel NIC 82599 SR-IOV on AWS does not provide the API required for the 10 Gbps SR-IOV interfaces.
- Changing the instance type of a vNIOS for AWS instance from an R4 EC2 shape to R6 can impact the services enabled on the instance as changing the shape refreshes the hardware ID (HWID)/serial number of the instance that is used to generate licenses.
- You cannot change the LAN1 private IP address in vNIOS for AWS.
- If you try to edit a scheduled upgrade configuration and have configured the IPv4/IPv6 gateway to be automatic, AWS-based Grid members running IPv4/IPv6 networking go offline for several minutes and may restart unexpectedly. This is because AWS does not support automatic gateway configurations. AWS networking operates using a DHCP client and therefore, an explicit gateway IP address must be provided.
- When DNS Infrastructure Protection (formerly called as Advanced DNS Protection/Threat Protection in versions of NIOS previous to 9.0.8) is enabled on a vNIOS instance that is configured with dual mode (IPv6 and IPv4 addresses) or an IPv6 only mode, the DNS service is interrupted because of packet drops caused by DNS Infrastructure Protection. To prevent this:
  - Get the latest ruleset by enabling **Automatic Download of Ruleset** or by manually uploading the latest ruleset.
  - Add a custom rule using each of the following templates and specifying the IP address of the LAN1 gateway in the **RULE PARAMETERS** field.
    - **WHITELIST PASS UDP IP for DHCP responses**
    - **WHITELIST PASS UDP IP for DHCPV6 responses**  
For detailed instructions, refer to the *Creating Custom Rules* section in the *[Infoblox NIOS Documentation](https://docs.infoblox.com)*.
- vNIOS for AWS does not support IPv6 addresses on MGMT interfaces because the IPv6 gateway is a unique local address (ULA).
- vNIOS instances deployed in AWS China do not support Amazon Route 53 integration, vDiscovery, and AWS API proxy configuration.

# Limitations Specific to HA

- vNIOS for AWS instances do not support HA configuration over IPv6 networks.
- vNIOS for AWS instances do not support HA setup with nodes on different cloud platforms, regions, availability zones, or on different instance types such as node 1 on a physical appliance and node 2 on a virtual appliance.
- The time taken for an HA failover can vary depending on the response time from the AWS API.
- vNIOS for AWS does not support automatic upgrade of software (NIOS) on an HA node If the node is running on a version of NIOS that is prior to 9.0.4.
- Before NIOS 9.1.0, vNIOS for AWS HA deployments supported only IMDSv1 (AWS Instance Metadata Service v1). Starting from NIOS 9.1.0, vNIOS supports IMDSv2.