CCTA common mistakes
CCTA · Understand the traps and how to avoid them.
Interpreting an empty filtered capture as proof no packet exists anywhere
The point, filter, context, address family, translation, or timing may not match.
What to do instead
Verify the actual flow and capture assumptions before drawing a global conclusion.
Using an unbounded debug during a production incident
Collection can consume CPU and disk and expose sensitive data.
What to do instead
Scope the test and define duration, size, protection, and stop conditions.
Treating an existing route as security authorization
Forwarding selection and policy permission are distinct conditions.
What to do instead
Check routing, enforcement, translation, endpoint response, and the return path separately.
Matching only the original private tuple on every capture
NAT and VPN encapsulation can change the visible packet at different points.
What to do instead
Map the expected pre-translation, post-translation, and outer observations.
Equating a published session with installed gateway policy
Publication and target deployment are separate stages.
What to do instead
Verify the correct package, target-specific task result, and actual gateway policy status.
Resetting trust before establishing a SIC-related cause
Reinitialization changes state and may interrupt component communication.
What to do instead
Check identity, connectivity, time, certificate evidence, and the precise error first.
Treating a green tunnel as a complete application test
Keys can exist while selectors, routes, policy, or endpoints still prevent delivery.
What to do instead
Test and observe the actual protected application in both directions.
Using a native-ESP-only filter for every VPN
NAT traversal can change the visible outer transport.
What to do instead
Verify actual encapsulation and peer endpoints before selecting capture fields.
Calling a normal standby member failed solely because it is not active
Expected role behavior depends on the configured availability mode.
What to do instead
Correlate the mode, member states, pnotes, interfaces, and synchronization evidence.
Using an overall average to exclude every performance bottleneck
Short bursts, one instance, a link member, or a queue can be constrained.
What to do instead
Use relevant time resolution and per-path evidence correlated with the actual workload.