Category: Security

“SSL Handshake failed for TCP” in LTM log on F5

Any F5 BIG-IP connected to the internet will be generating this log message a ton in /var/log/ltm:

01260013:4: SSL Handshake failed for TCP x.x.x.x:x -> y.y.y.y:443

This is simply an informational message indicating the peer closed the connection before completing the handshake. As this provides little to no information, you can often safely filter this from the LTM log by creating a log filter.

Continue reading

Using NFQUEUE to build your own firewall

Before we dive in, let me preface by stating that there are obviously pre-built firewalls (both free and commercial) which will be much more performant and secure. However, this should not stop you from building your own firewall: it’s both fun and educational! I’ll be using a Raspberry Pi to build the firewall, but you can use any Linux based OS.

Continue reading

Copyright © 2022 ForwardProxy

Theme by Anders NorenUp ↑