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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

Configure On-Demand Routing (ODR) on Cisco routers


ODR is used to allow hub routers to accept prefix information, distributed via Cisco Discovery Protocol (CDP) , from spoke routers.


On the hub router, enter this command
router odr

Also, routes can be controlled with a distribute-list:
distribute-list 10 in
distribute-list 20 out
assuming the referenced ACLs exist, otheriwse no routes are accepted or sent.

Since the prefix updates are carried on CDP, ODR updates can be controlled, in true sledgehammer fashion, by disabling CDP on an interface:interface serial 0/0
no cdp enable

For ODR to work properly, all dynamic routing protocols need to be disabled on the spoke routers.

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