Deepak Prasad

Troubleshoot 389 Directory Server replication errors: capture a baseline, diagnose connectivity TLS and bind failures, enable debug logging, and choose retry repair or reinitialize.

Monitor 389 Directory Server replication with dsconf: check agreement status, topology, CSNs and lag, analyze access logs, and configure alerts.

Remove stale supplier replica IDs from the 389 Directory Server RUV with dsconf repl-tasks cleanallruv, monitor tasks, abort safely, and understand force-cleaning risks.

Learn how to check ML-KEM support in TLS, create ML-DSA signatures, and verify post-quantum SSH key exchange on Linux, with tested Rocky Linux examples.

Manage the 389 Directory Server replication changelog with dsconf set-changelog, trim retention, compact-db, export and import, and encryption while preserving recoverability.

Enable DNS over TLS on RHEL 10.1 or later with NetworkManager, dnsconfd, and unbound, then verify upstream DNS uses encrypted TCP port 853.

Configure fractional replication in 389 Directory Server with dsconf. Exclude attributes from incremental and total updates and prevent empty updates.

Remove a consumer, hub, or supplier from a 389 Directory Server replication topology without losing updates, isolating replicas, or leaving stale RUV metadata.

Promote or demote a 389 Directory Server replica with dsconf, then verify replica IDs, agreements, replication health, client routing, and rollback.

Initialize or reinitialize a 389 Directory Server replica online or offline, monitor status, tune timeouts, and avoid overwriting destination data.

Replace password-based 389 Directory Server replication with certificate-based authentication using certmap.conf, a replication bind group, temporary bootstrap credentials, and SSLCLIENTAUTH agreements over LDAPS.

Manage 389 Directory Server replication agreements with dsconf repl-agmt to create, inspect, modify, schedule, verify, and delete individual agreements.

Configure a 389 Directory Server supplier, read-only hub, and consumer with dsconf, then initialize both replication hops and verify end-to-end cascading replication.

Configure 389 Directory Server multi-supplier replication with two writable suppliers, bidirectional agreements, initialization, testing, and failover.

Learn how 389 Directory Server replication works: supplier, consumer, and hub roles, replica ID, CSN, RUV, topology types, consistency limits, and how to choose single-supplier, multi-supplier, or cascading designs.

Configure a writable 389 Directory Server supplier and read-only consumer with dsconf, then initialize, verify, and troubleshoot replication.

When a Linux VM shows the wrong time after every reboot, trace the clock from the virtual RTC through chrony, identify the selected NTP source, and fix stale RTC values, unsuitable chrony sources, or hypervisor time-sync …

pidstat from the sysstat package reports per-process and per-thread CPU, memory, disk I/O, and context-switch statistics on Linux. Use it to find which PID is driving load during an incident.

mpstat from the sysstat package reports per-processor CPU utilization, NUMA node stats, and interrupt rates on Linux. Use it to find hot CPUs, IRQ load, and uneven scheduling across cores.

Migrate 389 Directory Server from Berkeley DB to LMDB with backend detection, dsctl dblib bdb2mdb, disk planning, validation, replicated rolling conversion, manual LDIF fallback, and recovery.

Migrate 389 Directory Server to a new host with replication or LDIF, including schema, TLS, validation, client cutover, and safe source removal.

Back up and restore 389 Directory Server with dsconf backup create, dsctl db2bak, checksum verification, off-host copies, systemd automation, and isolated restore testing.

Migrate OpenLDAP to 389 Directory Server with openldap_to_ds, LDIF preprocessing, schema and ACI mapping, validation, and cutover.

Create root suffixes and sub-suffixes with dsconf backend create, inspect backends, set read-only or disabled state, and delete a backend safely in 389 Directory Server.

Benchmark 389 Directory Server searches, binds, and writes with reproducible LDIF data, ldclt workloads, dsconf metrics, and logconv access-log analysis.

Configure Kerberos service principals, keytabs, SASL identity mapping, and GSSAPI authentication in 389 Directory Server with kinit and ldapwhoami.

Inspect and restrict TLS protocol versions and cipher suites in 389 Directory Server, test LDAPS and STARTTLS compatibility, and roll back safely.

Create custom 389 Directory Server attributes and auxiliary object classes with dsconf, schema LDIF files, reload tasks, validation, and replication-safe deployment.

Configure 389 Directory Server database links with dsconf chaining, proxy bind accounts, remote ACIs, LDAPS and StartTLS, failover settings, controls, monitoring, and troubleshooting.

Tune 389 Directory Server worker threads, listener threads, per-connection limits, idle timeouts, and file descriptors with dsconf and monitor output.