Don’t panic! False-positives from GuardDuty and Network Load Balancer (NLB)

False positives in AWS GuardDutyIf you’re keeping in touch with new services provided by AWS, you probably heard about new security monitoring tool: GuardDuty. You probably also noticed a whole new family of Elastic Load Balancers (v2), which includes Network Load Balancers (NLB). Deploying those two new services may generate some unexpected results – and here’s why.

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DHCP implementation in… PHP

PHP is not usually used to implement network services – and generally for good reasons. Not because it can’t be done, but rather because it’s not what it was meant to be used for.
Although, if you think that PHP simply can’t be used for anything other than serving your blog, think again. Because my DHCP implementation in PHP seems to work quite well!

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NAT, pf & jails

Sometimes you want to use jails on the same hosts that do the NAT. That of course isn’t by any means a complicated task and pf can do that very easily. The problems begin when you want to connect from one jail to a NATed IP (in the example 192.168.122.251) to a port that is redirected to another jail on the same system. Here is one of the solutions.

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