FMC Home Lab RAM: What Ran Beside a 32 GB FMCv on One Host
Built in my home lab: FMCv held 32 GiB of a 63 GiB host. IOL, IOSv-L2, ASAv and one-FTDv labs ran beside it; a dual-FTDv boot left FMC unhealthy for 183 s.
Firewall
Stateful inspection, policy design and traffic control at the perimeter. Articles tagged Firewall cover rule structure, NAT interaction and the packet path through the box.
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Cisco ZBF Self Zone: Why One Zone-Pair Broke OSPF and BGP
SSH stayed reachable while unicast OSPF and loopback eBGP failed on IOSv. This Containerlab home lab follows the timer expiries, ineffective OSPF inspection, reverse-policy trap, and verified repair with OSPF pass and stateful TCP/ICMP.
FMC REST API: Change FTD Rules and Deploy with curl and Python
The script saved TCP/8080 in FMC, but FTD still blocked it. This home lab follows the pending policy, measured token expiry, a failed deployment and the Python fix that completed deployment and restored HTTP.
FTD Transparent Mode in FMC: Bridge Group, BVI and Zone Fault
The bridge stayed up and ARP resolved the server, but ping and HTTP failed. In this FMC-managed FTDv home lab, one bridge member in the wrong Switched zone removed the intended deployed permits. Restoring its zone and deploying restored traffic.
FMC File Policy Attached but Not Blocking? Check the Rule's Application Protocol
An attached FMC file policy let a complete HTTP ZIP download pass because its rule selected FTP. Follow the saved rule, matching hashes, empty events, HTTP correction, and two verified ZIP resets in my home lab.
FTD File Policy in FMC: Why ZIP Downloads Pass Until It's Attached
A ZIP block policy existed in FMC, but Allow-Web did not use it. This home lab follows the full download, empty File Events, policy attachment, and verified ZIP resets while PDF and TXT stayed intact.
FMC Intrusion Policy with Snort 3: Why “Would block” Still Allows HTTP
A Snort 3 local rule set to Block still allowed HTTP in Detection mode. Follow the FMC event, real requests, and server captures, then change only Inspection Mode to Prevention and verify selective blocking.
Cisco FTD Twice NAT in FMC: Fix Swapped Destination Objects
An FMC twice NAT edit broke requests to both partner addresses. Follow real HTTP tests, UN-NAT phases, ASP drops and captures, then restore OLD-to-NEW destination translation and interface source PAT in the same rule.
FTD NAT in FMC: Auto NAT vs Manual NAT Rule Order
A server’s inbound static NAT still worked, but its partner API calls reset. In my home lab, broad manual PAT before Auto NAT changed the outbound source to 10.42.20.1. Moving equivalent PAT after Auto NAT restored 10.42.20.5.
FMC Deployment History: Roll Back a Bad FTD Deployment
A disabled Allow-Web rule broke HTTP after deployment. FMC Deployment History restored traffic, but the saved policy stayed disabled. Follow the rollback, prove recovery, then reconcile FMC before the next deploy.
FTD Packet Tracer Says Allow, but Traffic Fails: Capture in FMC
Curl timed out while FTD packet-tracer and FMC Unified Events said Allow. Inside/outside captures with Trace exposed the missing reply; restoring the server return route brought back the TCP handshake and HTTP 200.
FMC Prefilter Policy: Why Fastpath Skips ACP and Snort
A broad FMC prefilter Fastpath rule let client-b bypass an explicit ACP block and opened port 8080 for both clients. Real HTTP tests, packet-tracer and Unified Events show why Analyze restored access control in this home lab.