Category

System Administration Guides and Best Practices - Page 5

Learn system administration with practical guides on user management, services, monitoring, performance tuning, and Linux server management.

The System Administration section focuses on keeping Linux servers reliable, observable, and fast under real workloads.

These tutorials cover identity and access, remote administration, file services, install-time networking, monitoring, and day-two operations on production systems. Whether you are onboarding a new VM or chasing a latency spike, the guides below are written to be run on a live host with copy-paste commands and expected output.

Core administration topics

User and permission management, package updates, service units, log review, and backup planning all belong here. You will also find networking setup, firewall basics, and storage tasks that sit between a fresh install and a service that is ready for traffic.

For command-line fundamentals that every admin needs first, start with Linux — file management, permissions, and process control — then return here for server-focused workflows.

Performance tuning and troubleshooting

Many readers arrive looking for performance guidance: kernel tuning, I/O schedulers, memory limits, and tooling that explains what the machine is doing under load.

GoLinuxCloud covers practical tuning with articles such as sysctl settings for high-performance servers, Tuned profiles on Linux, Transparent Huge Pages, changing the I/O scheduler, and perf for performance analysis. For capacity checks, see guides on memory usage per process and disk type detection.

Application-level monitoring is covered in APM tools, and Kubernetes-specific limits appear in resources such as ulimit in pods.

Who this section is for

Linux administrators, site reliability engineers, and developers who own production hosts use these guides during incidents and planned maintenance. The steps are tested on common enterprise distributions and call out when behavior differs between families.

When you need packet-level diagnosis or directory services, explore Networking and the dedicated OpenLDAP course material linked from the site menu.

Browse the articles below for step-by-step administration guides and best practices.

214 articles

System administration category illustration with server rack, services, and monitoring graphics
Editor's picks
system-administration

Encrypt Sensitive Attributes in 389 Directory Server

Enable per-backend attribute encryption in 389 Directory Server with dsconf backend attr-encrypt, export and reimport with dsctl ldif2db --encrypted, verify LDAP access, and plan certificate and replication dependencies.

Deepak Prasad12 min read
system-administration

Configure Read-only Databases and Instances in 389 Directory Server

Enable and disable backend and instance read-only mode in 389 Directory Server with dsconf, verify LDAP result code 53 on writes, recover from dse.ldif, and avoid replication mistakes.

Deepak Prasad8 min read
system-administration

Configure LDAP Referrals in 389 Directory Server

Configure default, smart, suffix, and replication LDAP referrals in 389 Directory Server with dsconf, ldapmodify, client tests, security notes, and cleanup.

Deepak Prasad15 min read
system-administration

Configure Class of Service (CoS) in 389 Directory Server

Configure pointer, indirect, and classic Class of Service (CoS) in 389 Directory Server with tested LDIF examples, qualifiers, verification, and cleanup.

Deepak Prasad17 min read
system-administration

389 Directory Server Roles vs Groups: Differences and Use Cases

Compare groups with managed, filtered, and nested roles in 389 Directory Server. Learn how nsRole, memberOf, and dynamic membership differ.

Deepak Prasad14 min read
system-administration

Rename and Move LDAP Entries in 389 Directory Server

Rename LDAP entries, move users between OUs, and rename subtrees in 389 Directory Server with ldapmodify modrdn records, deleteOldRDN, newSuperior, and dsidm rename helpers.

Deepak Prasad16 min read
system-administration

Run a 389 Directory Server Instance as a Non-root User

Prepare a custom Directory Server root with dscreate ds-root, add administration wrapper scripts to PATH, create an unprivileged ldap-dev instance on ports above 1024, and manage it with user-specific dsctl commands.

Deepak Prasad12 min read
system-administration

Run Multiple 389 Directory Server Instances on One Host

Plan, create, and manage multiple 389 Directory Server instances on one host with unique names, LDAP ports, suffixes, systemd units, and client profiles.

Deepak Prasad16 min read
system-administration

389 Directory Server Architecture and Core Concepts

Understand 389 Directory Server architecture, including instances, ns-slapd, suffixes, backends, LMDB databases, schema, plug-ins, configuration, and replication.

Deepak Prasad14 min read
system-administration

OpenLDAP vs 389 Directory Server: Key Differences

Compare OpenLDAP and 389 Directory Server across installation, administration, access control, replication, plugins, performance, migration, and use cases.

Deepak Prasad20 min read
system-administration

Configure OpenLDAP Indexes with olcDbIndex

Configure OpenLDAP MDB indexes with olcDbIndex, map LDAP filters to index types, build indexes online, rebuild them with slapindex, and measure search performance.

Deepak Prasad19 min read
system-administration

Migrate Local Linux Users and Groups to OpenLDAP

Migrate local users and groups to OpenLDAP on RHEL, Rocky Linux, AlmaLinux, Oracle Linux, and CentOS Stream while preserving UID, GID, passwords, groups, and file ownership.

Deepak Prasad29 min read
security

Configure OpenLDAP sudo Rules with SSSD on RHEL Family

Configure OpenLDAP sudoRole policies with SSSD on RHEL, Rocky Linux, AlmaLinux, Oracle Linux, and CentOS Stream clients.

Deepak Prasad19 min read
security

Fix OpenLDAP Invalid Credentials Error 49

Fix OpenLDAP Error 49 for wrong bind DNs, passwords, userPassword ACLs, locked accounts, expired passwords, SSSD cache, PAM, and SSH authentication.

Deepak Prasad18 min read
system-administration

Configure OpenLDAP memberOf and Referential Integrity Overlays

Configure OpenLDAP memberOf and refint overlays for groupOfNames membership, reverse membership lookup, and automatic reference cleanup.

Deepak Prasad15 min read
security

Fix OpenLDAP Insufficient Access Error 50

Fix OpenLDAP Error 50 for ldapadd, ldapmodify, ldapdelete, password changes, cn=config, and no-write-access-to-parent ACL failures.

Deepak Prasad26 min read
security

Configure OpenLDAP Password Policy with ppolicy

Configure OpenLDAP ppolicy for password expiration, warnings, history, account lockout, grace logins, forced resets, and SSSD client behavior.

Deepak Prasad26 min read
system-administration

OpenLDAP Backup and Restore with slapcat and slapadd

Back up and restore OpenLDAP cn=config and all MDB databases using slapcat, slapadd, systemd timers, retention, checksums, and tested recovery.

Deepak Prasad33 min read
security

OpenLDAP ACL Configuration with Practical Examples

Configure OpenLDAP olcAccess ACLs for passwords, users, groups, SSSD, entry and children permissions, with safe testing and rollback.

Deepak Prasad29 min read
system-administration

OpenLDAP cn=config and MDB Explained with ldapmodify Examples

Understand OpenLDAP cn=config and MDB, discover numbered database DNs, query modules and overlays, and safely modify settings with ldapmodify.

Deepak Prasad25 min read
system-administration

Manage OpenLDAP Users and Groups with LDIF

Add, search, modify, rename, reset passwords, manage group membership, and delete OpenLDAP POSIX users and groups using LDIF.

Deepak Prasad23 min read
system-administration

Configure OpenLDAP Client with SSSD on RHEL-Based Linux

Configure OpenLDAP client authentication with SSSD, authselect, StartTLS, and automatic home directories on RHEL, Rocky Linux, AlmaLinux, Oracle Linux, and CentOS Stream.

Deepak Prasad16 min read
system-administration

OpenLDAP vs Active Directory: Complete Comparison Guide

OpenLDAP vs Active Directory in plain language: LDAP protocol vs directory services, OpenLDAP vs LDAPS, Samba AD vs Microsoft AD, cost, GPO, Kerberos, Linux integration, and when to choose each.

Deepak Prasad14 min read
system-administration

Create Central Authentication Server with OpenLDAP and NSLCD in Ubuntu

In this tutorial we will cover the steps to install and configure OpenLDAP from scratch and then use the OpenLDAP server as a central authentication server

Deepak Prasad10 min read
system-administration

Install and Configure OpenLDAP on Ubuntu [Step-By-Step]

OpenLDAP is an open-source implementation of the Lightweight Directory Access Protocol (LDAP). It's widely used for managing directory information, providing

Deepak Prasad9 min read
system-administration

Migrate OpenLDAP to a New Server on RHEL Family

Migrate OpenLDAP configuration, schemas, directory data, TLS files, and client endpoints to a new RHEL, Rocky Linux, AlmaLinux, Oracle Linux, or CentOS Stream server.

Deepak Prasad20 min read
system-administration

Configure OpenLDAP Multi-Provider Replication on RHEL-Based Linux (Multi-Master)

Configure OpenLDAP multi-provider or multi-master replication with server IDs, accesslog, delta-syncrepl, StartTLS, MirrorMode, and conflict testing on RHEL-family Linux.

Deepak Prasad22 min read
system-administration

Configure OpenLDAP Provider-Consumer Replication on RHEL-Based Linux (Master-Slave)

Configure one-way OpenLDAP provider-consumer replication with Syncrepl and StartTLS on RHEL-based Linux, including Rocky and AlmaLinux.

Deepak Prasad16 min read
security

Configure OpenLDAP TLS on RHEL-Based Linux

Configure OpenLDAP TLS on RHEL, Rocky Linux, AlmaLinux, Oracle Linux, and CentOS Stream using a private CA, StartTLS, LDAPS, and cn=config.

Deepak Prasad21 min read
system-administration

Install and Configure OpenLDAP on RHEL-Based Linux

Install OpenLDAP 2.6 on RHEL-based Linux, configure MDB with cn=config, create the base DIT, and verify local and remote LDAP searches.

Deepak Prasad17 min read