CV0-003 · Question #934
A company migrated its entire retail marketplace system to the cloud. The company is currently running a three-tier architecture on a Virtual Private Cloud (VPC) with web, database, and application se
The correct answer is B. Router table mismatch. The traceroute output reveals a sharp latency spike at the final hop to the database server, indicating that a routing table misconfiguration is sending traffic through a suboptimal or incorrect path between subnets.
Question
A company migrated its entire retail marketplace system to the cloud. The company is currently running a three-tier architecture on a Virtual Private Cloud (VPC) with web, database, and application servers on separate segments using virtual servers as compute resources. After the migration, users reported the following issues:
Slow-loading web pages Connection timeouts that are resolved after retries Given the following statistics:
[root@ApplicationServer]* traceroute DBserver traceroute to DBserver (192.168.10.2), 30 hops max, 60 by packets 1 gateway (192.168.11.1) 2.341 ms 3.77 ms 3.716 ms 2 nexthop (192.168.10.1) 2.5 ms 2.80 ms 2.36 ms ... 3 nexthop (192.168.10.2) 95 ms 97 ms 98 ms Which of the following is the best explanation for these issues?
Options
- AVPC firewall configuration
- BRouter table mismatch
- CLoad balancer
- DDatabase server virtual networking interface
How the community answered
(49 responses)- A12% (6)
- B55% (27)
- C8% (4)
- D24% (12)
Why each option
The traceroute output reveals a sharp latency spike at the final hop to the database server, indicating that a routing table misconfiguration is sending traffic through a suboptimal or incorrect path between subnets.
A VPC firewall misconfiguration drops or blocks packets outright rather than introducing elevated but stable latency, and retries would not consistently resolve a firewall-denied connection.
A router table mismatch causes traffic to follow an incorrect inter-subnet path - the application server (192.168.11.x) and DB server (192.168.10.x) are on adjacent subnets, but a misconfigured route forces packets through additional hops, producing the jump from under 3ms at hop 2 to 95-98ms at hop 3, which explains both the slow page loads and the connection timeouts that resolve on retry as the routing path stabilizes.
A load balancer issue would manifest as uneven distribution of requests across backend servers, not as a specific latency spike at a particular routing hop visible in traceroute output.
A DB server virtual NIC problem would produce consistent packet loss or connection refusals at that host, not the uniformly elevated 95-98ms round-trip times shown across all three traceroute probes.
Concept tested: VPC routing table misconfiguration causing inter-subnet latency
Source: https://docs.aws.amazon.com/vpc/latest/userguide/VPC_Route_Tables.html
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