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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

Upgrade Linux Kernel


You need to compile kernel only if:
=> You need custom made kernel for specific task such as embedded kernel.
=> Apply third party security patches.
=> You need to apply specific patch to Linux

Upgrade of the kernel in Red Hat enterprise Linux version <= 4.x

If your system is registered with Red Hat Network (RHN), then you can use the up2datecommand as follows:
# up2date -f kernel
For SMP kernel (multi core or multiple CPU) use command:
# up2date -f kernel-smp

Upgrade of the kernel in Fedora Linux / CentOS / RHEL 5

Use yum command to upgrade kernel:
# yum update kernel
If you have downloaded RPM file use rpm command:
# rpm -ivh kernel*

Upgrade of the kernel in Debian or Ubuntu Linux

Use apt-get command. First find your kernel version:
$ uname -r
Next find available kernel images:
$ apt-cache search linux-image
Now install kernel by explicitly specifying version number:
# apt-get install linux-image-x.x.x-xx
OR
$ sudo apt-get install linux-image-x.x.x-xx


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