CCNA Db Mgmt Ops Questions

Option A is correct because using eventually consistent reads consumes only half the RCUs compared to strongly consistent reads, effectively doubling the read capacity. Option B is wrong because DynamoDB Accelerator (DAX) is an in-memory cache that can reduce read load but does not directly address the RCU consumption for reads that still hit the table. Option C is wrong because increasing RCUs would solve throttling but increase costs unnecessarily if eventually consistent reads suffice.

Option D is wrong because decreasing RCUs would worsen throttling.

Option A is correct because high evictions indicate the cache is full, leading to item removal and low hit ratio. Option B is wrong because high latency does not directly cause evictions. Option C is wrong because insufficient replication factor does not cause evictions.

Option D is wrong because encryption in transit does not affect cache performance.

Option B is correct. The Deny statement applies to the source IP 10.0.1.5 (within 10.0.0.0/8), overriding the Allow. Option A is wrong because the IAM role does allow s3:GetObject on the bucket.

Option C is wrong because there is no explicit condition on the Allow statement. Option D is wrong because the policy is attached to the role, not an SCP.

Option B is correct because the 'Deny' statement only applies to the 'rds:DeleteDBInstance' action, not to 'rds:DeleteDBSnapshot'. The 'Allow' statement explicitly allows 'rds:DeleteDBSnapshot' on all resources. Since there is no explicit deny for deleting snapshots, the allow takes effect.

Option A is incorrect because the deny only applies to deleting instances, not snapshots. Option C is incorrect because the policy does not deny snapshot deletion. Option D is incorrect because the developer is allowed to delete snapshots.

Option A is correct because ReplicationLatency is the metric for global tables. Option B is incorrect for this purpose. Option C is incorrect because it is a custom metric.

Option D is incorrect because it is for RDS.

Option B is correct because MultiAZ is false and SecondaryAvailabilityZone is null, indicating it is not a Multi-AZ deployment. Option A is wrong because the Engine is mysql, not aurora. Option C is wrong because it is not Multi-AZ.

Option D is wrong because the instance is available, not in a failed state.

Option C is correct because DynamoDB auto scaling can adjust capacity based on load, and because the traffic is predictable, scheduled scaling can be used to increase capacity during the campaign and reduce costs otherwise. Option A is wrong because on-demand is more expensive for predictable workloads. Option B is wrong because increasing RCU manually may lead to overprovisioning.

Option D is wrong because DAX does not reduce read capacity consumption; it caches reads but still counts against RCU if not cached.

Option B is correct because after a failover, the DNS record is updated to point to the new primary, but the application may be using cached DNS. Checking CloudWatch metrics for connection counts and latency can help identify the issue. Option A is wrong because forcing a reboot would not resolve DNS caching.

Option C is wrong because RDS manages the secondary instance automatically. Option D is wrong because restoring from backup is unnecessary.

Option D is correct because using a hash-based shard key on vehicle_id distributes writes evenly and reduces index maintenance overhead. Option A is wrong because turning off journaling reduces durability, not index maintenance. Option B is wrong because increasing instance size adds CPU but does not address the root cause.

Option C is wrong because removing the compound index harms query performance.