Case Studies

Problem: Client requested a step‑by‑step procedure to add two new servers to an existing three‑node Kafka cluster running in KRaft mode, with the explicit requirement to avoid any data loss. The cluster’s existing configuration (server.properties) and current controller.quorum.voters format were provided for reference. The observable concern was that adding voters and brokers incorrectly could cause […]

Problem: The data mount was approaching full capacity. Investigation showed that the keyspace-level backups directories inside the Cassandra data directories were consuming the majority of space (≈150 GB). No active snapshots were present on the cluster when the issue was reported. The cluster configuration had incremental_backups: true in cassandra.yaml because the customer wanted to retain […]

Problem: A Patroni-managed PostgreSQL cluster (PostgreSQL 15.8, Patroni 2.1.4) was reporting sustained high memory consumption on a host with ~275 GB of physical RAM and only ~8% free. The environment had HugePages enabled at the OS level. Patroni configuration showed shared_buffers=68GB, work_mem=20MB, max_parallel_workers_per_gather=4 and max_connections=2000. Observed behavior included consistently ~90% system memory utilization across a […]

Problem: A MySQL table named with embedded spaces (schema-qualified as “dbo.Sourcing Id Master”) could not be used in the Debezium connector’s message.key.columns setting. The connector configuration contained the entry “message.key.columns”: “dbo.Sourcing Id Master:id” and the connector validation rejected it with an invalid-format error referencing the expected pattern for message.key.columns. Attempts to escape characters in the […]

Problem: An application UPDATE statement against a partitioned PostgreSQL table (UPDATE tab1 SET sys_update_date = $1, agg_status = $2, output_filename = $3, merge_type = $4 WHERE period_key = $5 and record_id = $6) experienced consistent slowdowns in a nightly early‑morning window. The customer reported that partition file sizes showed normal small footprints for partitions p1–p12, […]

Problem: Applications using Redisson MapCache began throwing RedisResponseTimeoutException errors (client timeout = 3000 ms) during eviction activity. Errors were raised while executing EVALSHA with context pointing to org.redisson.eviction.MapCacheEvictionTask; application threads were reporting “Unable to evict elements” outputs correlated with redisson-timer-* threads. Environment details: a Redis Cluster (client traffic on shard port 7000) served multiple integration […]

Problem: A production team requested guidance to implement multi-tenancy and fine-grained RBAC in Apache NiFi so different users/groups would have isolated view and edit rights at the Process Group level. Requested capabilities included: allowing certain users to view and edit only a specific Process Group (no access to other canvas areas), defining Read‑Only vs Read/Write […]

Problem: The customer reported degraded performance in a PostgreSQL query joining multiple views and tables, including V_CDD_PRF_PARTY_PARTY_R_DRF. Although the outer query applied a highly selective filter (C.FIRST_PARTY_KEY = 'CDD000248470'), the PostgreSQL optimizer did not push this predicate into the view. As a result, the view was fully evaluated, leading to increased CPU usage, higher I/O, […]

Problem: A customer reported a critical production issue related to incorrect timestamp values in a data pipeline built using Debezium CDC. Timestamps originating from an MSSQL source system were appearing +05:30 hours ahead of the expected values in the downstream system. The issue affected multiple tables containing timestamp columns based on MSSQL date and time data types that do not […]