Cisco ASA Routed Mode vs Transparent Mode
Cisco ASA can run in two firewall modes: routed mode, where the firewall is a Layer 3 hop with its
8 min read
ASA
Cisco Adaptive Security Appliance, the stateful firewall platform that has anchored enterprise perimeters for two decades and is now being succeeded by Secure Firewall (FTD). Articles tagged ASA cover security levels, NAT 8.3+ and twice NAT, ACLs, AnyConnect SSL and IKEv2 VPN, site-to-site IPsec, failover, packet-tracer, hardening, and ASAv 9.x lab walkthroughs.
42 posts
Cisco ASA Common Outage Scenarios and Fixes
Every Cisco ASA that runs long enough hits a small set of repeatable failure modes: a NAT pool exhausting, an
8 min read
Cisco ASA Connection Table and xlate Table Troubleshooting
The Cisco ASA tracks two layered tables that explain almost every "is this traffic flowing" question: the connection
9 min read
Cisco ASA asp-drop Counters Explained
The Cisco ASA's accelerated security path (ASP) is the data-plane fast path that handles every forwarded packet after
8 min read
Cisco ASA Packet Capture from CLI
Packet capture from the Cisco ASA CLI is the highest-resolution diagnostic tool you have. When show conn, show xlate, and
8 min read
Cisco ASA Stateful Failover and Interface Tracking
Stateful failover is the option that turns a Cisco ASA active/standby pair into something users actually do not notice
7 min read