Juniper Updated JN0-232 Exam Questions and Answers by abbas

When troubleshooting packet handling on an SRX Series device, administrators need to understand exactly how theflow moduleis processing traffic. The most effective tool for this is theflow traceoptions feature.

Flow traceoptions:Provides detailed per-packet trace information showing each processing step within the flow module. It reveals how traffic is evaluated against session tables, NAT rules, and security policies. This is the recommended method for in-depth troubleshooting.

Why not the others?

Theflow session table(Option A) shows only active sessions and counters, not detailed step-by-step handling.

Theforwarding table(Option B) relates to routing and forwarding decisions, not flow security processing.

Firewall filters(Option D) can match and log traffic but do not display detailed flow processing steps.

Therefore, the correct method to get detailed information about flow handling is toenable flow traceoptions.

Static NAT:Provides a one-to-one bidirectional mapping between internal and external IP addresses. When configured, the translation automatically applies in both directions (Option A is correct). It does not use Port Address Translation (Option C is incorrect).

Destination NAT:Allows external clients to access internal resources by translating the destination address. It supportsport forwardingso specific services (e.g., HTTP on port 80) can be forwarded to an internal host (Option D is correct). It does not require equal-sized address ranges (Option B is incorrect).

Correct Characteristics:Static NAT is bidirectional, and Destination NAT supports port forwarding.

Functional zones(e.g., junos-host, management, null) are not used for forwarding transit traffic. They are used to manage traffic destined to or from the SRX device itself.

Option A:Correct. If traffic enters through a functional zone interface, it is meant for the SRX, not for transit, so it cannot exit another interface.

Option D:Correct. Transit interfaces handle forwarding traffic, but they cannot send that traffic out through a functional zone interface.

Option B and C:Incorrect, because functional zones are strictly control-plane, not transit forwarding zones.

Correct Statements:A and D

The packet processing order in SRX with NAT and policies is:

Destination NAT(applies first, for inbound traffic).

Security Policy Evaluation(after destination NAT, before source NAT).

Source NAT(applies last, for outbound traffic).

Option A:Incorrect. Policies are not evaluated before destination NAT.

Option B:Correct. Security policies are evaluatedbefore source NATbut after destination NAT. So in terms of order, policies are processed prior to source NAT.

Option C:Incorrect. Policies are not evaluated before source NAT — they are evaluatedbefore source NAT is applied.

Option D:Correct. Policies are evaluatedafter destination NAT.

Correct Statements:B and D