Practice Free JN0-232 Security, Associate (JNCIA-SEC) Exam Questions Answers With Explanation

The antivirus feature on SRX relies on signature definition files that must be regularly updated. To check the status of these updates, the correct operational command is:

show security utm anti-virus status(Option D). This displays details such as:

Antivirus engine status

Last update time of virus definitions

Version of the signature database

Other options:

Content-filtering statistics (Option A) shows counters for file-type filtering, not antivirus updates.

Anti-spam status (Option B) shows spam filtering engine connectivity.

Web filtering status (Option C) shows SBL/web filter server connection details.

Correct Command:show security utm anti-virus status

When a packet enters an SRX interface, aroute lookupis performed:

It determines theegress interface(Option B) by checking the destination IP against the routing table.

Once the egress interface is known, its associatedegress security zone(Option D) is also determined.

Theingress interface (Option A)is already known when the packet arrives, so the route lookup does not determine it.

DNS name (Option C):DNS is unrelated to routing lookups.

Correct Results:egress interface, egress security zone

Adding interfaces (Option A):An interface must be assigned to a security zone before it can pass traffic. By default, interfaces are in the null zone and cannot send or receive traffic.

Exception traffic (Option B):Security zones define host-inbound-traffic settings, which determine what types of management or control-plane traffic (SSH, ICMP, SNMP) are permitted.

Routing instances (Options C and D):Security zones arespecific to a routing instanceand cannot include interfaces from multiple instances. Therefore, interfaces in the same zone cannot belong to different routing instances.

Correct Statements:A and B

Juniper SRX evaluatessecurity policiessequentially from top to bottom. Once a policy match is found, no further policies are evaluated. In this exhibit:

First Policy (FTP, deny):

Source: 172.25.11.0/24

Destination: 10.1.0.0/16

Application: FTP

Action: deny?Any FTP traffic from 172.25.11.0/24 to 10.1.0.0/16 isdenied.

Second Policy (SSH, permit):

Same source/destination but application = SSH

Action = permit?SSH traffic from 172.25.11.0/24 to 10.1.0.0/16 ispermitted.

Third Policy (HTTPS, permit):?HTTPS from the same source/destination ispermitted.

Fourth Policy (Ping, permit):

Source: 172.25.11.0/24 to any destination

Application: ping

Action: permit?ICMP echo requests (ping) from 172.25.11.0/24 to any destination arepermitted.

Fifth Policy (any ? any, deny):?Serves as a defaultdeny allat the end.

Now checking each option:

Option A:SSH from 172.25.11.10 ? 10.1.0.10 matches theSSH permit rule(second policy).?Correct.

Option B:Ping from 172.25.11.100 ? 10.1.0.10 matches theping permit rule(fourth policy). This traffic is permitted, not denied.?Incorrect.

Option C:FTP from 10.1.0.10 ? 172.25.11.100 isreverse traffic (untrust to trust). The table applies onlytrust ? untrust, so this policy does not apply.?Incorrect.

Option D:FTP from 172.25.11.11 ? 10.1.0.10 matches the first policy (FTP deny rule).?Correct.

Correct Statements:A, D

From the exhibit:

The user attempted to access https://www.wikipedia.org.

The block page indicates:

CATEGORY: NG_Reference

REASON: BY_PRE_DEFINED

The header states:“Juniper Web Filtering has been set to block this site.”

Analysis of options:

Option A:Correct. The log shows “REASON: BY_PRE_DEFINED,” which means the site was blocked because it matched apredefined categoryin the Web filtering database.

Option B:Correct. The category “NG_Reference” indicates that theNextGen (Enhanced/Cloud-based) Web Filtering typeis being used.

Option C:Incorrect. The exhibit does not provide any information about SSL proxy configuration; it only shows that the HTTPS site was blocked.

Option D:Incorrect. The block page shown is the standard Juniper default block page, not a custom message.

Correct Statements:The URL matches a predefined Web filtering category, and the NextGen Web Filtering type is being used.

The packet flow fornew trafficon SRX is processed in a defined order:

Screens (Option B, Step 1):Packets are first checked by screens for anomalies such as floods, malformed packets, or protocol violations.

Route Lookup (Step 2):The destination IP is checked in the routing table to determine the egress interface.

Zone Determination (Step 3):Once the ingress and egress interfaces are known, their associated zones are identified.

Security Policies (Step 4):With both zones determined, the packet is evaluated against the configured security policies.

Other options list incorrect sequences, either moving routing later or placing policies before zone determination, which is not possible.

Correct Processing Order:screens ? routes ? zones ? security policies

PAT (Port Address Translation), also called NAT overload, allows many devices to share a single public IP:

Option C:Correct. Multiple internal hosts share a single external IP.

Option D:Correct. Each internal host is mapped to the same public IP but differentiated by unique port numbers.

Option A:This describes basic static NAT (1-to-1 mapping).

Option B:Incorrect, this describes general NAT behavior but not specific to PAT.

Correct Statements:PAT enables multiple internal devices to share one external IP, and it maps internal IPs to external IP + port.

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

From the exhibit, the content filter configuration is as follows:

Match Conditions:

Application:HTTP

Direction:download

File-types:exe

Action:

block

notification log

Analysis of Options:

Option A: Incorrect. The configuration specifies thedownload direction, not upload. Uploads of .exe files are unaffected.

Option B: Correct. Because the rule applies todownloads, .exe files will be blocked when users attempt to download them over HTTP.

Option C: Correct. The notification { log; } statement ensures that an entry will be added to the SRX device’s log when the action is triggered.

Option D: Incorrect. No configuration for sending e-mail notifications is shown in the rule. Only logging is specified.

Correct Statements:B and C

Security policies in Junos OS match traffic based on specific criteria:

Source and destination addresses(Option B).

Application(Option D), which may be defined as services (e.g., tcp/80) or recognized through AppID.

Other options:

MAC addresses(Option A) are not used in policy matching; policies operate at Layer 3/4.

Interface name(Option C) is used in firewall filters, not in security policy definitions.

Correct Criteria:Source address and Applications

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.

Intra-zone traffic:On SRX devices, traffic between interfaces in the same security zone is allowedwithout requiring a security policy(Option C is correct). Policies are only evaluated for inter-zone traffic.

Junos-host functional zone:This zone is a predefined functional zone that allows administrators to apply policies controlling access to the SRX firewall itself, such as SSH, HTTP, or SNMP traffic (Option D is correct).

Null zone:This zone is a predefined discard zone. Interfaces placed in the null zone drop all traffic. It does not allow policy logging of dropped control plane traffic (Option A is incorrect).

Management functional zone:This is used to define management interfaces, not the “functional zone” as stated in Option B (incorrect wording).

Correct Statements:C and D

Transit traffic is defined as traffic that passesthroughthe SRX (not destined to the Routing Engine). To capture transit traffic:

Sampling and port mirroring (Option D)are the correct supported methods for capturing or exporting transit traffic. Sampling allows captured packets to be sent to a file or collector, while port mirroring sends a copy to a monitoring interface.

Option A:Firewall filters on an egress interface cannot directly capture packets; they can only count, accept, discard, or sample. Sampling itself is separate.

Option B:Loopback interface (lo0) is for control-plane traffic, not transit traffic.

Option C:tcpdump is not supported on SRX as a tool for capturing transit packets; the operational command monitor traffic interface is used, but sampling/port mirroring is the recommended scalable approach.

Correct Method:Sampling and port mirroring

Global policies (Option D):Evaluated before zone-based policies. They allow centralized control and can apply across all zones. Perfect for Internet-to-private traffic that must be enforced before other rules.

Routing policy (Option A):Controls routing decisions, not traffic forwarding/security.

Default policy (Option B):Denies all traffic by default, but cannot be customized for early evaluation.

Zone policy (Option C):Zone-based policies apply after global policies and are limited to specific zone pairs.

Correct Policy Type:Global policy