This is my new concept for DNS security with Bind9, Pi-hole and OpenDNS in my network. Bind9 is used as Enterprise DNS to resolve hostnames and IP addresses in the local area network, Pi-hole and OpenDNS are used for Internet DNS traffic. DNS traffic is passed by Cisco ASA Firewall ACL.
Setup of two redundant Cisco ASA firewalls on a Fritzbox cable modem with Non-routed transfer network to keep the "PC-MAC"/"exposed host" configuration on Fritzbox during ASA failover switching
Replacing faulty memory for Cisco ASA-5520, checking memory and failover
Cisco ASA5520 stuck at Booting system, please wait... and how to check for faulty memory
Blocking Facebooks networks on ASA firewall
A simple bash script to create ASA Firewall rules from Talos IP Blacklist