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VMware on AWS - How to restore NSX DFW firewall rules to previous state

Customers who uses NSX day-in, day-out would like to have a point-in time restore functionality of DFW firewall rules. Many customer have a large footprints in VMC and make changes to DFW quite often. This feature was missing for long time and we could see its included in recent versions . Let's see how DFW configuration roll back works  NSX DFW configuration has versioning, and it is stored in the NSX Manager.  Every time when someone update DFW configuration, NSX creates one more version but keep storing the previous ones. You can rollback for previous config but reapplying it once again.  You can find the options under Networking & Security tab , > Security > Distributed Firewall . In the right side we see an Actions drop down. Choose View to get to the below screen.  Let’s go through the use case:  1. Original state- default config with no custom rules:  a. There are no saved configurations during last 30 days: In my existing test setup, with the current setting


The Hot Standby Router Protocol, HSRP, provides a mechanism which is designed to support non-disruptive failover of IP traffic in certain circumstances. In particular, the protocol protects against the failure of the first hop router when the source host cannot learn the IP address of the first hop router dynamically. The protocol is designed for use over multi-access, multicast or broadcast capable LANs (e.g., Ethernet). HSRP is not intended as a replacement for existing dynamic router discovery mechanisms and those protocols should be used instead whenever possible. A large class of legacy host implementations that do not support dynamic discovery are capable of configuring a default router. HSRP provides failover services to those hosts.

Using HSRP, a set of routers work in concert to present the illusion of a single virtual router to the hosts on the LAN. This set is known as an HSRP group or a standby group. A single router elected from the group is responsible for forwarding the packets that hosts send to the virtual router. This router is known as the active router. Another router is elected as the standby router. In the event that the active router fails, the standby assumes the packet forwarding duties of the active router. Although an arbitrary number of routers may run HSRP, only the active router forwards the packets sent to the virtual router.

To minimize network traffic, only the active and the standby routers send periodic HSRP messages once the protocol has completed the election process. If the active router fails, the standby router takes over as the active router. If the standby router fails or becomes the active router, another router is elected as the standby router.

On a particular LAN, multiple hot standby groups may coexist and overlap. Each standby group emulates a single virtual router. For each standby group, a single well-known MAC address is allocated to the group, as well as an IP address. The IP address SHOULD belong to the primary subnet in use on the LAN, but MUST differ from the addresses allocated as interface addresses on all routers and hosts on the LAN, including virtual IP addresses assigned to other HSRP groups.

If multiple groups are used on a single LAN, load splitting can be achieved by distributing hosts among different standby groups.

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