DNS Archives - Page 2 of 2

Systems Admin

Configure a Domain Controller as a Global Catalog Server

How to add the Global Catalog flag to an existing Domain Controller in Active Directory Sites and Services, and the PowerShell equivalent (one bit on the NTDS Settings options attribute via Set-ADObject). Walks the GUI three-click path, the Set-ADObject cmdlet, post-change verification with Get-ADDomainController IsGlobalCatalog / dsquery server -isgc / repadmin /options / Test-NetConnection on port 3268, the partial-attribute-set replication timing caveat, and the common pitfalls (right-clicking the wrong tree node, leaving only one GC, demoting accidentally).

Systems Admin

Active Directory Health Check with PowerShell

One PowerShell script that wraps dcdiag, Test-Connection, Resolve-DnsName, w32tm, Get-Service, and CIM into a single colored HTML report — one row per Domain Controller, 35 columns of pass/warn/fail per cell. Includes the full Get-ADHealth.ps1 source, what each dcdiag test actually catches (Connectivity, SysVolCheck, KccEvent, FSMOCheck, NCSecDesc, etc.), how to schedule a daily SMTP-emailed run, the MotW / Unblock-File / ExecutionPolicy gotchas, and the green-DNS-red-everything-else fingerprint that means a DC is offline.

Linux Admin

Linux Networking Errors: 10 Common Connection Problems and Fixes

Working reference for the 10 most common Linux networking errors. Connection refused vs timed out (RST vs silent drop), No route to host, NXDOMAIN DNS failures (dig +short / resolv.conf / nsswitch), SSL certificate verify failed (expired / CN mismatch / clock skew), Network unreachable, Address already in use (EADDRINUSE with ss -tlnp 'sport = :PORT'), TIME_WAIT exhaustion, ARP resolution, SSH permission denied (publickey). Each error covers description, root cause, and step-by-step fix using the OSI-ladder diagnostic order. Cross-linked to the Linux networking command reference and the advanced-networking-errors deep-dive.

Systems Admin

Install Active Directory Domain Services on Windows Server

Step-by-step guide to installing the Active Directory Domain Services (AD DS) role on Windows Server and promoting the machine to the first Domain Controller in a new forest. Covers the Add Roles and Features wizard, the Configuration Wizard, DSRM password, DNS delegation warning, paths, the auto-generated PowerShell script, and post-promotion verification.

Systems Admin

Implement and Manage IPAM (IP Address Management)

Learn how to implement and manage IPAM (IP Address Management) on Windows Server. This step-by-step guide covers installing the IPAM feature, provisioning with Group Policy-based provisioning, configuring server discovery, setting servers to Managed status, applying IPAM GPOs with Invoke-IpamGpoProvisioning, retrieving data, and using the IP address space, DHCP scope, and DNS zone management capabilities.

Systems Admin

Implement Domain Name System Security Extension (DNSSEC)

Learn how to implement DNSSEC on Windows Server to protect against man-in-the-middle DNS attacks. This step-by-step guide covers the Zone Signing Wizard, configuring Key Signing Keys (KSK) and Zone Signing Keys (ZSK) with RSA-SHA-256, enabling NSEC3 and Trust Anchor distribution, verifying the padlock icon, and best practices for key rotation and monitoring.

Systems Admin

Configure DNS Forwarding: Regular and Conditional Forwarders

Learn how to configure DNS forwarding in Windows Server DNS Manager. This step-by-step guide covers regular forwarding (offloading all external queries to public DNS servers like 8.8.8.8) and conditional forwarding (routing domain-specific queries to designated DNS servers), including the DNS resolution order and Active Directory replication for conditional forwarders.

Systems Admin

Configure and Manage Active Directory Sites and Services

Learn how to configure Active Directory Sites and Services for a multi-site environment. This step-by-step guide covers creating AD sites, configuring site links with costs, setting the replication interval and schedule, mapping IP subnets to sites, and managing site link bridging for efficient domain controller replication.

Systems Admin

Configure Active Directory to Support Additional Domain Names

Add an alternative UPN suffix to your AD forest so users can sign in as user@infotechninja.com without renaming the domain. Walks the optional internal DNS zone, the AD Domains and Trusts registration, the per-user assignment, and the Microsoft 365 hybrid pre-flight (domain verification, UPN audit, sign-in mode). Includes the Set-ADForest / Set-ADUser PowerShell equivalents and the common mistakes (wrong right-click, suffix vs email, forgetting public DNS validation).

Systems Admin

Create Trust Relationship Between Active Directory Forests

Learn how to establish a two-way forest trust between independent Active Directory forests. This guide covers DNS conditional forwarding setup, the New Trust Wizard, authentication scope selection, and SID filtering considerations.

Systems Admin

How to Configure DNS Reverse Lookup Zones and PTR Records on Windows Server

Learn how to configure DNS reverse lookup zones and PTR records on Windows Server. This step-by-step guide covers zone creation, dynamic registration, manual PTR records, and verification — essential for email delivery, SIEM tools, and network troubleshooting.

Tag: DNS