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

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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

What is an SNTP?

The Simple Network Time Protocol (SNTP) is a simpler version of the Network Time Protocol (NTP). SNTP synchronizes the time between networked computer systems and is relied on when data is being transferred via the Internet. The NTP protocol is one of the most established protocols still used on the Internet. It uses a GPS or radio clock to tell time and is accurate past the seconds place.
Why is the SNTP Necessary?
The need for precise time synchronization has continued to increase with the evolution of computer technology over the past several decades. In the networking field, network servers and their client computers require precision to the millisecond and beyond in order to ensure data file transfers occur without errors. Computers also require specific time synchronization in order to ensure data packet and email delivery in the proper sequence to destination networks and email recipients. The importance of the SNTP and NTP protocols exponentially expands with the number of computers that are on a network in order to prioritize network traffic appropriately.
Computers that Use the SNTP Protocol
Servers are the primary SNTP protocol users. Servers use the protocol in order to keep the time on network services and client computers synchronized based on Internet standards. Web servers that put a heavy demand on traffic may have to switch to the NTP for time service requirements. However, the SNTP protocol is suitable for providing the time for all services and client computers on small to medium networks.
What are the Security Implications of the SNTP Protocol?
The SNTP protocol’s data is subject to packet sniffing since it is plain text that is transmitted over a local network and the Internet without encryption. It may also be susceptible to a dictionary or brute force attack in order to guess the authentication and encryption keys and strings. The protocol also uses the UDP communications protocol, which may be open to IP spoofing attacks.

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