Wintel Admin - Interview Q &A

1) Introduce yourself and walk through your daily responsibilities

Answer (sample — tweak to your background):
“I’m a Windows Server & virtualization administrator with X years of experience across AD, DNS/DHCP, SCCM/ConfigMgr, and VMware vSphere. In my current role I manage ~N Windows servers (2016–2022), support monthly patching via SCCM ADRs, automate routine tasks with PowerShell, and maintain our vSphere clusters (HA/DRS, Lifecycle Manager patching). Day to day, I handle incident tickets, troubleshoot access and performance issues, keep our environment compliant with baselines (CIS, AV, WSUS/SUP), and work on small projects—like server builds, in‑place upgrades, and file server migrations. I collaborate closely with network and security teams on firewall rules, certificate renewals, and vulnerability remediation. Recently, I led a Windows Server 2019→2022 upgrade wave and standardized our ADR patching windows, improving patch compliance from X% to Y%.”

What they listen for: scope/scale, core tools, repeatable processes, collaboration, and a recent improvement you drove.

2) User can’t access a shared drive — troubleshooting steps

Short structure: Identify who/what/where (user vs. server vs. network vs. permissions).

Confirm basics

Repro & path: \\fileserver\share vs. mapped drive.
Try another device/user to isolate user vs. share.
Check recent password change / account lockout.

Connectivity & name resolution

PowerShell

Test-NetConnection fileserver -Port 445

nslookup fileserver

ipconfig /flushdns

Session/credential cleanup

BAT

net use * /delete

cmdkey /list

klist purge :: if Kerberos issues suspected

Permissions

Check NTFS vs. Share permissions; look for deny ACEs, groups, token bloat.
Validate Effective Access with user’s groups.

Server-side checks

Event Viewer (SMBServer/Operational), Get-SmbSession, Get-SmbOpenFile.
If DFS, test referral target directly.

Policies & security

GPO changes (gpresult /r), AV/ransomware protections, SMB signing/encryption requirements.
Recent firewall or NAC changes.

Wrap-up: “I’d isolate whether it’s identity, network (445), name resolution, or authorization, and collect logs before escalating.”

3) How updates are received in SCCM and how you deploy them

Concept flow: Microsoft Update → WSUS/SUP → SCCM sync → SUG/ADR → DPs → Client scan & install.

Software Update Point (SUP) integrates WSUS with SCCM. SUP syncs metadata from Microsoft Update on a schedule.
I use Automatic Deployment Rules (ADRs) to create Software Update Groups (SUGs) per ring (Pilot/Prod), with deadlines, user experience, and maintenance windows set.
Content is downloaded to Deployment Packages and distributed to Distribution Points (DPs).
Clients scan via WUA and report compliance.
I monitor WSyncMgr.log (site), WUAHandler.log / UpdatesDeployment.log / UpdatesHandler.log / ScanAgent.log (client), and Compliance dashboards.
For out-of-band patches, I do a manual SUG, test on Pilot, then staggered rollout.

4) Steps to provision a new server

Build-runbook outline:

Plan: request/task, sizing, OU, IP/VLAN, DNS/DHCP, firewall rules, backup scope, monitoring.
Create VM (vSphere): template with baseline hardening (local policy, NTP), proper datastore/cluster.
OS & identity: join domain, place in OU; apply baseline GPOs.
Patching: ensure SCCM client installed and device in correct collections; update fully.
Roles/Features: Server Manager/PowerShell; least privilege for service accounts (gMSA/dMSA if applicable).
Security: AV/EDR, local firewall, JEA or RBAC, disable SMBv1, TLS 1.0/1.1 if required, LAPS/Windows LAPS.
Monitoring/Backup: add to monitoring (SCOM/Prometheus/LogicMonitor), backup jobs, and CMDB.
Validation: functionality, failover (if cluster), handover docs & ticket closure.

5) In‑place upgrade Windows Server 2019 → 2022

When: Supported for many roles; avoid for domain controllers hosting legacy features or when major app vendors require clean install.

Steps:

Pre‑checks: app/vendor support, disk space, drivers/firmware, snapshots/backup, disable AV real-time during setup, remove unsupported roles/features.
If a Failover Cluster: use Cluster OS Rolling Upgrade—pause & drain roles, upgrade node, patch, validate, resume, repeat node-by-node.
Run setup from 2022 media → choose “Keep files, apps, and settings” → allow Dynamic Update → reboot.
Post: winver, re-enable AV, update VMware Tools, reinstall out-of-box drivers if needed, verify roles (AD/DNS/DHCP/File).
Backout: snapshot or full-image restore plan.

6) Windows Server versions you’ve worked on & the latest available

Sample: “I’ve administered Windows Server 2012 R2, 2016, 2019, and 2022 in production. The current LTSC release is Windows Server 2025; Microsoft lists it as the current LTSC with availability on Nov 1, 2024.” [learn.microsoft.com], [microsoft.com]

7) Default port numbers for RDP and DNS

RDP: TCP 3389 (and UDP 3389 if enabled).
DNS: UDP 53 (queries) and TCP 53 (zone transfers/large responses).

8) How to perform a host upgrade (VMware ESXi example)

Assumption: vSphere environment with Lifecycle Manager (VUM/LCM).

Prep: check HCL (server, NIC/HBA firmware), confirm vCenter/ESXi interop, backup vCenter and host config, review acceptance level & 3rd‑party VIBs.
Baseline/Image: import ISO or create LCM image; attach to cluster/host.
Evacuate host: vMotion VMs, Maintenance Mode (ensure DRS), verify no orphaned VMs/lock files.
Upgrade: Remediate via LCM (preferred) or boot from ISO for standalone hosts.
Post‑checks: exit maintenance mode, verify VMkernel adapters, vDS uplinks, storage paths (MPIO), time/NTP, and reinstall vendor tools (if any).
Roll through cluster with admission control observed; monitor HA/DRS health.

9) Vulnerabilities you’ve remediated

Examples (tailor to your history):

Disabled SMBv1, enforced SMB signing/encryption where needed.
Enforced NLA on RDP, restricted RDP exposure, hardened TLS (disable 1.0/1.1, prioritize strong cipher suites).
Fixed AD risks: stale privileged accounts, weak Kerberos pre-auth, enforced LAPS/Windows LAPS for local admin rotation.
Addressed known issues like PrintNightmare (point-and-print restrictions), and regular OS/CU patching via SCCM.
Remediated DNS and IIS configuration findings from vulnerability scans (headers, obsolete ciphers).
Approach: validate CVEs, test patches, staged rollout, and verify with rescans.

10) Purpose of VMware Tools

Optimized paravirtualized drivers (VMXNET3, ballooning).
Guest-OS awareness: clean shutdown/restart, IP/CPU/memory reporting.
Time sync option (used selectively; usually NTP is authoritative).
Enables features like quiesced snapshots and Guest Operations.

11) Difference between a Cumulative Update (CU) and a Servicing Stack Update (SSU)

CU = monthly rollup with all security/quality fixes to date.
SSU = updates the servicing stack (the component that installs updates) to improve reliability of applying CUs.
Since Feb 2021, for Windows 10/Server 2004+, Microsoft bundles SSU with the LCU so you deploy one package (WSUS/ConfigMgr handle the order automatically). [learn.microsoft.com]
Microsoft’s IT Pro guidance documents the transition to one combined payload in WSUS/ConfigMgr. [techcommun...rosoft.com]

12) Server not responding to ping; can’t RDP — what next & who to contact first

Triage path:

From hypervisor: open VM console (vSphere/Hyper‑V) to see if OS is up (BSOD/hang), check CPU/memory pressure, storage latency.
Inside OS (if console works):
- Check Windows Firewall profiles, recent GPOs, NIC status/IP, route print, ipconfig /all.
- Verify security tools (EDR) didn’t isolate.
If console unreachable but host is fine: check port-group/VLAN, NIC link, MAC/ARP conflicts, DHCP scope, recent ACL/firewall changes.
Contact: After hypervisor/OS checks, if network symptoms persist (no ARP, wrong VLAN, blocked gateway), engage the Network team first with evidence (MAC/ARP tables, switch port, traceroute). If it’s OS/firewall, keep it within the Server team.

13) What is High Availability (HA) and how it works (VMware)

VMware HA restarts VMs on other hosts if a host fails.
Uses management network heartbeats and datastore heartbeats to detect isolation/host failure.
Admission Control ensures spare cluster capacity to restart VMs.
RTO = typically minutes (time to detect + boot). No state continuity (VMs reboot).

14) What is Fault Tolerance (FT) and why used

VMware FT provides zero‑downtime protection by running a primary & secondary VM in lockstep; if the host fails, the secondary takes over instantly.
Used for select low‑latency or mission‑critical workloads where even brief downtime is unacceptable.
Trade‑offs: higher resource overhead, networking requirements, and vCPU limits by edition.

15) Patch not being pushed to a server — troubleshooting

Client-side (SCCM):

Health: ccmexec running; ccmrepair if needed.
Logs: WUAHandler.log, UpdatesDeployment.log, UpdatesHandler.log, PolicyAgent.log, ScanAgent.log, CAS.log, ContentTransferManager.log, DataTransferService.log, LocationServices.log.
Check Maintenance Window, deadline, and whether device is in the correct collection; trigger: Machine Policy Retrieval & Evaluation, Software Updates Scan Cycle.
Verify WSUS scan not failing (error codes), content download, and free disk space (CCMCache).

Server-side (SCCM/SUP):

WSyncMgr.log (sync OK), ADR evaluated, content on DPs, boundaries/boundary groups, SUP health, and no expired SUP certs.
Confirm the update is deployed to that collection and not superseded or expired.

16) How to increase disk space and CPU resources on a server

Disk (VM on vSphere):

Expand VMDK (thin/thick as per policy).
Inside Windows: Disk Management or diskpart to extend the volume (ensure GPT for >2TB).
For clustered disks or special filesystems, follow vendor steps; ensure backups/snapshots removed or accounted for.
Validate app paths/log rotation after expansion.

CPU/Memory:

Add vCPU/RAM (hot‑add if enabled; otherwise schedule a reboot).
Monitor CPU Ready/Co‑Stop, NUMA alignment; adjust shares/reservations/limits if contention in cluster.
Consider licensing (e.g., SQL per‑core) and application guidance before scaling.

Quick one‑page “reminder” phrases (for recall in the interview)

SCCM Updates: “SUP via WSUS → ADRs create SUGs → content to DPs → clients scan with WUA → deadlines within maintenance windows; monitor client & site logs.”
RDP/DNS: “3389; 53 UDP/TCP.”
Windows Server latest: “Current LTSC is Server 2025 (GA Nov 2024).” [learn.microsoft.com], [microsoft.com]
CU vs SSU: “CU = fixes; SSU = update engine; now bundled (since 2021) into one package.” [learn.microsoft.com]
HA vs FT: “HA = restart VMs; FT = continuous, zero downtime.”
Shared drive triage: “Name resolution → port 445 → credentials/sessions → NTFS vs Share perms → server logs.”

1) Introduce yourself & daily responsibilities

Answer (template):
“I’m a Windows Server & VMware admin with X years of experience across AD, DNS/DHCP, Group Policy, SCCM/ConfigMgr, and vSphere. I manage ~N Windows servers (2016–2022/2025), own monthly patching through SCCM ADR rings, automate with PowerShell, and maintain vSphere clusters (HA/DRS, Lifecycle Manager). I partner with network & security on firewall rules, certs, and vulnerability remediation. Recently, I led a 2019→2022 in‑place upgrade program and improved patch compliance from A%→B% with maintenance‑window discipline.”

Example you can narrate:

“Last quarter, I consolidated four legacy file servers into a new 2022 cluster, used Cluster OS Rolling Upgrade to avoid downtime, and moved quotas and NTFS ACLs with Robocopy /COPY:DATSOU /SEC. We reduced storage incidents by 30% and improved backup success to 99%.”

2) User cannot access a shared drive — steps

Answer (flow): Reproduce → connectivity (445) → name resolution → session cleanup → authorization → server logs.

Example:

“User A gets access denied to \\FS01\Finance. I confirmed path works for me, then:
1. Test-NetConnection FS01 -Port 445 (OK), nslookup FS01 (OK).
2. Cleared stale tickets: klist purge, removed mappings: net use * /delete.
3. Checked Effective Access—user lost access because Finance‑Group was removed from NTFS when we tightened share permissions. I re‑added the AD group (least‑privilege), asked the user to re‑logon—issue resolved.
4. Server‑side, I checked SMBServer/Operational logs and Get-SmbSession to ensure there weren’t denying conditions.”

3) How SCCM receives & deploys updates

Answer: SUP (WSUS) syncs metadata → ADRs build SUGs by rings → content to DPs → clients scan/install within maintenance windows → compliance reporting.

Example:

“We run a Patch Tuesday ADR that targets a Pilot collection (20 servers) with a 3‑day deadline and a Prod ADR with a 10‑day deadline. The ADR filters ‘Required’ updates, auto‑creates a Software Update Group, downloads to a “Windows Servers – Monthly” Deployment Package, and distributes to all DPs. I monitor WSyncMgr.log (site) and WUAHandler/UpdatesDeployment/UpdatesHandler logs (clients). Last month, two web servers missed content due to boundary group mis‑mapping; I fixed the boundary group, redistributed the package, and forced Software Updates Scan Cycle.”

4) Steps to provision a new server

Answer (runbook): Plan sizing & firewall → deploy VM from a hardened template → domain join & GPOs → SCCM client & patch to current → add roles/features → security baseline (AV/EDR, LAPS, disable SMBv1) → monitoring & backup → handover.

Example:

“For a new IIS node: I cloned from our 2022 hardened template, joined domain OU Servers\Web, applied IIS + URL Rewrite with PowerShell DSC, created a gMSA for the app pool, added Nagios/SCOM monitoring, registered in the F5 pool after health‑check passed, and documented in CMDB with a rollback snapshot for 48 hours.”

5) In‑place upgrade 2019 → 2022

Answer: Validate app/vendor support → backup/snapshot → remove unsupported roles → run setup.exe (keep apps & settings) → Dynamic Update → reboots → post‑checks (VMware Tools/drivers, services, AV). For clusters, use Cluster OS Rolling Upgrade node‑by‑node.

Example:

“I upgraded a 2‑node file cluster. Paused & drained Node‑1, snapshot, in‑place upgraded to 2022, patched, validated CSV ownership & SMB shares, resumed; repeated on Node‑2. Total service interruption ~30 seconds when roles failed over during drain/resume.”

6) Windows Server versions you’ve worked on & latest available

Answer (fill in your history):
“I’ve managed Windows Server 2012 R2, 2016, 2019, 2022, and started rolling out 2025. The current LTSC release is Windows Server 2025 (availability listed as Nov 1, 2024 on Microsoft’s release info).”
Context: Microsoft announced Windows Server 2025 general availability in early November 2024. [learn.microsoft.com] [microsoft.com]

Example:

“We tested SMB over QUIC and Hotpatching via Azure Arc on a pair of 2025 file servers in a DMZ lab before planning broader adoption.” (Windows Server 2025’s status as current LTSC and its features are described on Microsoft docs and announcements.) [learn.microsoft.com], [microsoft.com]

7) Default ports for RDP & DNS

Answer:

RDP: TCP 3389 (plus UDP 3389 if enabled).
DNS: UDP 53 (queries) & TCP 53 (zone transfers/large responses).

Example:

“A branch site couldn’t resolve HQ zones; the firewall allowed UDP 53 but not TCP 53, so large responses & AXFR failed. After opening TCP 53, resolution stabilized.”

8) Performing a host upgrade (VMware ESXi)

Answer: Validate HCL/interop → LCM image/baseline → evacuate host (vMotion) → Maintenance Mode → remediate/upgrade → post checks (vDS, vmk NICs, paths, time) → exit Maintenance Mode → roll through cluster.

Example:

“Upgrading a 4‑host cluster, I attached a Lifecycle Manager Image with ESXi build X, put Host‑1 in Maintenance Mode, Remediate, verified vmk0 on mgmt VLAN and storage paths, exited Maintenance, and continued host‑by‑host. We kept Admission Control at 1 host failure to ensure capacity.”

9) Vulnerabilities you’ve remediated

Answer (pick 3–5 you’ve actually done):

Disabled SMBv1, enforced SMB signing/encryption where required.
RDP hardening: NLA, restricted exposure via jump hosts, and login rate‑limit via GPO.
AD hygiene: removed stale privileged accounts, deployed Windows LAPS for local admin rotation; tightened service accounts to gMSA/dMSA.
Print spooler & point‑and‑print hardening; TLS 1.0/1.1 disabled, strong cipher suites only.

Example:

“Our scanner flagged legacy RC4 ciphers on IIS. I pushed a GPO to disable weak ciphers & protocols, coordinated a Blue/Green rollout on web nodes, and validated with Qualys rescans—risk closed.”

10) Purpose of VMware Tools

Answer: Optimized drivers (VMXNET3, balloon), guest/host integration (clean shutdown, IP reporting), time sync option, quiesced snapshots, guest operations.

Example:

“After installing Tools on a legacy 2012 R2 VM, we switched to VMXNET3, cutting CPU usage on a busy NIC by ~10–15% and improving throughput.”

11) CU vs SSU (and the bundling change)

Answer:

Cumulative Update (CU) = monthly rollup of security/quality fixes.
Servicing Stack Update (SSU) = updates the component that installs updates.
Since Feb 2021 (Windows 10/Server 2004+), Microsoft bundles SSU with LCU into a single package—simplifies WSUS/ConfigMgr deployments. [learn.microsoft.com]
Microsoft’s IT Pro guidance explains the one cumulative package flow for WSUS/ConfigMgr. [techcommun...rosoft.com]

Example:

“Our ADR targets ‘Latest Cumulative Update’ only. Because SSU is bundled, we no longer stage a separate SSU deployment. This eliminated the old ‘LCU not applicable’ failure when the SSU prerequisite was missing.” [learn.microsoft.com], [techcommun...rosoft.com]

12) Server not pinging; no RDP — what next & who first

Answer:

Check hypervisor console to see if OS is alive; if alive, inspect firewall profile, NIC status/IP, recent GPO, and EDR isolation.
If console is fine but no network, look for VLAN/ACL issues, ARP/MAC conflicts.
Contact first: If symptoms suggest network path (no ARP/gateway reachability), Network team; if Windows firewall/EDR, handle in the Server team.

Example:

“I opened the VM console—server was up but had a wrong VLAN on its port-group after a recent change. I moved it back to the correct pg‑Prod, restored connectivity, and then reviewed our change template to include port‑group validation.”

13) What is High Availability (HA) & how it works (VMware)

Answer: Cluster feature that restarts VMs on surviving hosts when a host fails; uses mgmt heartbeats + datastore heartbeats; Admission Control reserves capacity. RTO = minutes (reboot time).

Example:

“When Host‑3 died due to PSU, HA restarted 35 VMs across remaining hosts. Application teams saw 2–4 minutes of downtime while services rebooted.”

14) What is Fault Tolerance (FT) & why used

Answer: Runs primary & secondary VM in lockstep; zero‑downtime failover if host fails. Used for workloads where even seconds of downtime are unacceptable; trade‑offs: resource overhead, network bandwidth, feature limits.

Example:

“We enabled FT for a license server that breaks concurrent sessions if it restarts. FT kept it online during a host maintenance event with no session drops.”

15) Patch isn’t being pushed — steps

Answer (SCCM focus):

Client health (ccmexec, ccmrepair), correct collection & maintenance window, trigger Policy Retrieval & Scan Cycle.
Review logs: WUAHandler.log, UpdatesDeployment.log, UpdatesHandler.log, CAS.log, ContentTransferManager.log, LocationServices.log.
Server side: SUP sync OK, content on DPs, boundary groups correct, update not expired/superseded.

Example:

“A DB server kept reporting ‘0x8024401c’. LocationServices.log showed it pointing to a DP in a different boundary. I fixed the subnet object in the Boundary Group, redistributed the package, triggered a Software Updates Deployment Evaluation Cycle, and the update installed within 20 minutes.”

16) Increasing disk space & CPU on a server

Answer:

Disk: Expand virtual disk in hypervisor → inside Windows, extend volume (Disk Management or diskpart)—ensure GPT for >2 TB, consider app‑level steps for clustered/shared disks.
CPU/RAM: Add vCPU/RAM (hot‑add if enabled, or schedule reboot), check cluster contention (CPU Ready, Co‑Stop), and app licensing.

Example:

“For a SQL VM, I expanded the data VMDK from 500 GB → 800 GB, then used diskpart → select volume X → extend. We also added 2 vCPU, monitored CPU Ready to ensure it stayed <5%, and verified throughput with a baseline query set.”

Quick facts you might reference out loud (with sources)

“Windows Server 2025 is the current LTSC; Microsoft lists availability as Nov 1, 2024 on its release info page.” [learn.microsoft.com]
“Microsoft bundles SSU with the LCU for supported versions, so we typically deploy a single cumulative package each month.”

1) Introduce yourself & daily responsibilities — more example snippets you can add

Automation: “I wrote a PowerShell wrapper around Get-CimInstance Win32_QuickFixEngineering and SCCM’s WMI classes to export a weekly patch‑gaps report to Teams. That cut our ‘over‑30‑days’ non‑compliance by 18%.”
Capacity & performance: “I tuned a busy IIS farm by moving to VMXNET3, enabling Receive Side Scaling, and right‑sizing vCPU. The app’s 95th percentile latency dropped 22%.”
Cost control: “We reclaimed 7 TB by implementing log rotation and Robocopy archive rules on file servers; backup windows shrank by 40 minutes.”
Security hygiene: “I rolled out Windows LAPS and removed hard‑coded local admin passwords across 500+ servers within two weeks.”

2) Shared drive not accessible — additional examples

Kerberos token bloat: User is in too many AD groups; Effective Access shows allow, but token exceeds size → intermittent Access Denied. Temporary fix by removing redundant groups; long‑term: group flattening.
DFS referral split‑brain: \\corp\finance targets FS01 and FS02. User is referred to FS02 (stale ACLs) while others hit FS01. Force target: \\FS01\Finance, fix DFS link permissions/ordering.
Offline Files conflict: Laptop cached \\FS01\Finance while server share was moved to \\FS02. Disable Offline Files for that share via GPO and clear cache (Control Panel > Sync Center).
SMB signing policy drift: New GPO requires signing; legacy NAS share fails. Confirm via SMBClient/Operational logs; align NAS settings or scope the GPO.
Stale DNS: fs01 points to retired IP on one site DNS. nslookup fs01 shows bad record in branch; fix zone replication or flush caches.

3) SCCM/ConfigMgr updates — additional deployment examples

Phased deployment: Phase 1 (Pilot 2%), Phase 2 (Servers non‑prod 20%), Phase 3 (Prod 78%) with automatic transition after compliance ≥95% and no critical incidents.
DC/cluster exceptions: Create a separate SUG for DCs & SQL clusters with no auto‑reboots, install window with manual coordination, and a Pre/Post script to pause/resume cluster nodes.
Zero‑day out‑of‑band: Build an emergency SUG, bypass ADRs, Download > Distribute > Deploy to Pilot first, then prod with a 24‑hour deadline.
3rd‑party patching: Import catalog (SCUP/partner add‑on) for Java/Chrome; single SUG keeps browser CVEs under SLA.
Troubleshooting content: A DP failed content validation—ContentLibraryCleanup.exe + re‑distribute fixed “hash mismatch” errors.

4) Provisioning a new server — additional examples

SQL Server: Template deploy → domain join → enable instant file initialization, set TempDB size & files, configure gMSA for SQL Agent, add to AG listener, and monitor with custom PerfMon counters.
RDS host: Install RDSH, FSLogix profiles, set GPO for Fair Share, disable print redirection, and add to RD Collection with drain‑mode validation.
File server: Enable Access‑Based Enumeration, configure VSS with 3 restore points/day, FSRM quotas and file screens, and test restores.
Domain‑joined web server: IIS + ARR/URL Rewrite via DSC; import SSL cert from internal PKI; health probes on F5 before joining pool.

5) In‑place upgrade 2019 → 2022 — additional examples

Standalone application server: Stop the service, uninstall legacy filter drivers, run setup.exe with Dynamic Update, re‑enable AV after install, and verify event logs & app pools.
Domain Controllers (recommended approach): Instead of in‑place, add new 2022 DC, transfer FSMO roles, ensure SYSVOL healthy, let replication settle, then demote the 2019 DC. (Interviewers appreciate that you avoid in‑place on DCs.)
Failover Cluster (non‑CSV workloads): Pause & drain Role A → upgrade node → patch → resume → live‑migrate Role A back → repeat for Role B node. Validate Cluster Functional Level at the end.

6) Windows Server versions & current latest — additional examples

Your exposure: “Daily ops on 2016/2019/2022, pilot 2025 for file services and AD lab.”
Upgrade path story: “We moved an app from 2012 R2 → 2022 using side‑by‑side migration because the vendor required a clean install.”
Current latest statement: “The current LTSC is Windows Server 2025, listed as the current release on Microsoft’s Windows Server release information page (availability noted as Nov 1, 2024).” [learn.microsoft.com]
Context you can add: “Microsoft announced general availability of Windows Server 2025 in early November 2024; we’re evaluating features like SMB over QUIC and Hotpatch via Azure Arc.” [microsoft.com]

7) Default ports for RDP & DNS — additional examples

Non‑default RDP port: Hardened jump server listens on TCP 3390; Group Policy sets firewall rule; users connect via gateway—document the exception.
DNS large responses: A site blocked TCP 53; AD‑integrated DNS transfers and large EDNS responses failed until TCP 53 was allowed.
Split‑DNS scenario: Conditional forwarder to a partner domain needed both UDP/TCP 53 open across the inter‑site firewall.

8) Host upgrade (VMware ESXi) — additional examples

vCenter first: Upgraded vCenter via VAMI backup and ISO, then remediated ESXi hosts with Lifecycle Manager Image to keep interop compliance.
Quick Boot: Enabled Quick Boot on supported hosts to shave minutes off each remediation cycle.
Standalone host (no DRS): Scheduled outage, shut down non‑critical VMs, ISO upgrade, validated HBA firmware & drivers, powered VMs back up.
vSAN cluster: Upgraded ESXi first (don’t upgrade vSAN disk format until all hosts are on the new version), then run disk format upgrade during a low‑IO window.

9) Vulnerabilities you remediated — additional examples

LDAP signing/channel binding: Enabled per Microsoft guidance; tested app binds; closed scanner finding on DCs.
NTLM hardening: Reduced NTLM fallbacks, enabled SMB signing where mandated, and monitored NTLM traffic with security baseline GPOs.
Zerologon (CVE‑2020‑1472): Applied DC updates and set Full enforcement registry phase ahead of Microsoft’s deadline.
PrintNightmare: Disabled remote printing on servers; defined Point and Print Restrictions; patched spooler on print servers only.
IIS hardening: Disabled weak ciphers via GPO, set HSTS and request filtering; validated with Qualys and SSLLabs.
Credential Guard: Enabled on supported servers to reduce credential theft risk (especially on jump servers).

10) Purpose of VMware Tools — additional examples

Quiesced backups: Veeam snapshots failed without Tools; after installing Tools and enabling application‑aware processing, SQL backups became consistent.
Time sync strategy: Disabled Tools time sync on Domain Controllers (let them follow the AD time hierarchy); kept it on for non‑domain appliances.
Driver uplift: Migrated from E1000e to VMXNET3 after Tools install; saw lower CPU per Gbps and fewer packet drops on busy web tiers.

11) CU vs SSU (and bundling) — additional examples

Old failure mode: “Update not applicable” when the SSU prerequisite wasn’t installed before the LCU.
Today’s approach: On Windows 10/Server 2004+, the LCU includes the SSU, so in WSUS/ConfigMgr we deploy just the monthly CU package; the stack installs SSU→LCU in the correct order automatically. [learn.microsoft.com]
WSUS/ConfigMgr detail: Microsoft’s IT Pro guidance describes the single cumulative package published to WSUS for on‑prem management tools. [techcommun...rosoft.com]
Servicing repair case: Corrupt servicing stack fixed with DISM /Online /Cleanup-Image /RestoreHealth, then monthly CU installed successfully.

12) Server not pinging; can’t RDP — additional examples

Firewall profile flip: NIC changed to Public profile after a driver update; inbound rules blocked. Switched to Domain profile and re‑enabled ICMP rule.
Duplicate IP: ARP shows flapping MACs; tracked to a cloned VM that came up with the same static IP—fixed the clone and cleared ARP.
Disconnected vNIC: In vSphere, the “Connected” checkbox was unchecked post‑maintenance; re‑checked and restored connectivity.
Security isolation: EDR put the host in network isolation/quarantine; released from console and created a maintenance exclusion for patch windows.
Routing issue: Default gateway pushed by GPO conflicted with static route required for storage; route re‑ordered to restore reachability.
Who to call first: If hypervisor console is fine but there’s no ARP/gateway reachability → Network. If console shows Windows Firewall/EDR blocking → Server/SecOps first.

13) High Availability (VMware HA) — additional examples

Host isolation response: Management network lost; HA used datastore heartbeating to decide, then restarted VMs on surviving hosts.
Admission Control tuning: Moved from “1 host failure” to “%‑based” (25%) to better fit a 5‑host cluster after capacity changes.
APD/PDL behavior: When a storage array path went APD, VMs restarted on hosts with good paths due to HA datastore heartbeat loss.
DRS interplay: After HA restarts VMs, DRS rebalances load automatically; we pinned a latency‑sensitive VM to two hosts using VM‑Host rules.

14) Fault Tolerance (FT) — additional examples

License server: Protected a legacy license server with FT to avoid app session drops during host maintenance; zero downtime during a host reboot.
Co‑ordination with backups: Disabled app‑quiesced snapshots for FT VMs (not supported in some versions) and relied on agent‑level backups.
Limitations to mention: Higher CPU/memory/network overhead; vCPU count limits for FT VMs; careful storage/network planning required (interviewers like that you know the trade‑offs).

15) Patch not being pushed — additional examples

Pending reboot lock: UpdatesDeployment.log shows “Pending system restart” from an older install; a reboot allows new patches to deploy.
WUA corruption: 0x80070057 during scan—fixed by resetting Windows Update components and re‑registering DLLs, then rescanning.
Proxy/WSUS URL: Server in a DMZ can’t reach SUP via proxy; added proxy in client settings or set local override to SUP.
Overlapping boundaries: Client picks the “wrong” DP with no content; fixed by correcting boundary group precedence and DP affinity.
Expired/superseded: The SUG contained superseded updates; refreshed filters to “Required, not superseded” and ADR picked the right ones.
Content distribution: Package on one DP showed hash mismatch; re‑validated, re‑distributed, and watched PkgXferMgr.log for success.

16) Increasing disk/CPU/memory — additional examples

Disk (basic NTFS): Grew VMDK from 200 GB→400 GB; inside Windows:
PowerShell
Get-Partition -DriveLetter F | Resize-Partition -Size 400GB
ReFS data volume: Extended a ReFS volume for backup repository; verified block cloning still performed as expected after extension.
Clustered disk: Used Failover Cluster Manager to take resource offline, expanded LUN on array, rescanned disks on all nodes, brought resource online, then extended in Disk Management.
CPU scale‑up vs scale‑out: For IIS we added two more web nodes behind the load balancer instead of pushing a single VM to 16 vCPU (avoids co‑stop/ready time).
NUMA awareness: For a memory‑heavy SQL VM we aligned vCPU/RAM to stay within a physical NUMA node to reduce cross‑node latency.
Capacity guardrails: Checked CPU Ready and Co‑Stop metrics post‑change; rolled back a RAM increase that caused ballooning on a constrained cluster.

Quick facts you may restate (with sources)

“Windows Server 2025 is the current LTSC and is listed as the current release on Microsoft’s Windows Server release information page (availability shown as Nov 1, 2024).” [learn.microsoft.com]
“Microsoft bundles Servicing Stack Updates (SSU) with the monthly Cumulative Update (LCU) for Windows 10/Windows Server version 2004 and later, so we typically deploy just one package each month in WSUS/ConfigMgr.” [learn.microsoft.com], [techcommun...rosoft.com]

✅ DNS Issue Examples (deep dive)

Use a few that match your environment; mention the exact tool/log you’d check. Keep your answers crisp: symptom → triage → root cause → fix.

1) Stale A record after IP change

Symptom: Client resolves a server to an old IP; RDP/HTTP fails intermittently.
Confirm:
PowerShell
nslookup app01
ipconfig /displaydns | findstr /i app01
Resolve-DnsName app01 -Server 10.10.10.10 -Type A
Fix: Clear client cache (ipconfig /flushdns), update DHCP/DDNS or static DNS entry, enable scavenging on the zone, and reduce record TTL during migrations.

2) Reverse lookup missing (PTR not created)

Symptom: Monitoring or Kerberos mutual auth warnings; some apps using reverse DNS show “unknown”.
Confirm:
PowerShell
nslookup 10.10.20.25
Fix: Create the PTR in the matching reverse zone; ensure DHCP is authorized to update PTRs for dynamic clients.

3) Conditional forwarder mis‑pointed

Symptom: Queries for partner.local time out.
Confirm: Check forwarder IPs in DNS Manager; test from server:
PowerShell
Resolve-DnsName www.partner.local -Server <yourDNSServer> -Type A -NoRecursion
Fix: Correct the target DNS IPs; if across firewalls, allow UDP/TCP 53; validate recursion policy at the partner side.

4) Split‑brain DNS inconsistent (internal vs external)

Symptom: Internal users get a different IP (or wrong) than expected for portal.company.com.
Confirm: Compare:
PowerShell
Resolve-DnsName portal.company.com -Server <internalDNS>
Resolve-DnsName portal.company.com -Server 8.8.8.8
Fix: Align internal zone records with the intended internal VIP; document split‑brain behavior for helpdesk.

5) DNS over UDP fragmentation blocked (EDNS size)

Symptom: Some external domains fail to resolve; large DNSSEC/EDNS responses time out; ping works.
Confirm:
- Packet capture shows “truncated” bit; client doesn’t fall back to TCP due to firewall block.
Fix: Allow TCP 53 on the path; if needed, lower EDNS UDP packet size on DNS server; or fix MTU/fragmentation on WAN.

6) Zone transfer blocked (secondary zone expired)

Symptom: Secondary DNS shows stale records; event log shows IXFR/AXFR failures.
Confirm: On primary, review zone’s Zone Transfers tab; on secondary, dnscmd /zoneinfo.
Fix: Permit transfers to secondary’s IP, verify TSIG or allow lists, and open TCP 53 between name servers.

7) Delegation for child domain broken

Symptom: host.child.corp.local fails to resolve across sites.
Confirm: Verify NS and glue A records in the parent zone:
PowerShell
Resolve-DnsName child.corp.local -Type NS
Fix: Add/update delegation in the parent with correct NS and glue records; ensure child DC/DNS is reachable.

8) Root hints misconfigured / recursion disabled

Symptom: Internal DNS resolves internal zones but not internet names.
Confirm: DNS Manager → Server Properties → Root Hints; also check Recursion checkbox.
Fix: Restore default root hints or configure forwarders (e.g., ISP, public resolvers). Ensure recursion is allowed for clients.

9) AD‑integrated zone replication lag

Symptom: One site resolves new records; another site doesn’t.
Confirm:
PowerShell
Get-DnsServerZone -Name corp.local | fl ReplicationScope
repadmin /replsummary
Fix: Resolve AD replication errors; ensure the zone is replicated to the correct partition (domain-wide vs forest-wide).

10) Negative caching prolongs an outage

Symptom: A record was missing briefly; after adding it, some clients still fail.
Confirm:
PowerShell
ipconfig /displaydns
Fix: Flush caches on clients and DNS servers (Clear-DnsServerCache), temporarily lower TTL during changes.

11) LLMNR/NetBIOS name resolution confusion

Symptom: Short name (\\FILES) resolves to a random workstation on a flat network.
Confirm: Check client policy for LLMNR/NetBIOS; capture traffic (Wireshark shows LLMNR responses).
Fix: Disable LLMNR and NetBIOS over TCP/IP via GPO; require FQDNs or proper DNS suffix search lists.

12) DNSSEC validation failures (if enabled)

Symptom: Specific signed domains fail; “SERVFAIL” seen.
Confirm: Use a validating resolver to test; check KSK/ZSK rollovers timing.
Fix: Ensure trust anchors are current; resolve time synchronization issues; temporarily disable validation while fixing anchors.

13) Client pointing to wrong DNS server order

Symptom: Intermittent failures; clients sometimes query a DR DNS that can’t reach internet.
Confirm:
PowerShell
ipconfig /all
Get-DnsClientServerAddress -AddressFamily IPv4
Fix: Correct DHCP scope options or NIC static settings; ensure primary/secondary order and decommission any rogue DNS IPs.

14) Recursive query blocked by DNS policy or ACL

Symptom: Only certain subnets cannot resolve the internet.
Confirm: Review DNS Policies (Windows Server 2016+), firewall ACLs by subnet.
Fix: Adjust policy to allow recursion for those subnets; update firewall rules.

15) DFS/Namespace name resolution overlap

Symptom: \\domain.local\share gives “path not found” only for new sites.
Confirm: Test DFS referral:
PowerShell
dfsutil /pktinfo
dfsutil /spcinfo
Fix: Fix site association in AD Sites & Services; ensure DFS targets exist and have correct permissions.

✅ Patch / Update Failure Examples (Windows Server + SCCM/ConfigMgr/WSUS)

Think error code → where you look → one or two fixes. Mention specific logs—interviewers love that.

1) Pending reboot blocks new updates

Symptom: SCCM shows “Past deadline – Will retry” or Windows Update installs nothing.
Confirm: UpdatesDeployment.log mentions pending reboot; registry shows PendingFileRenameOperations.
Fix: Reboot; use a compliance baseline to detect and schedule reboots post‑install.

2) Low disk space in `SoftwareDistribution`/`CCMCache`

Symptom: Error 0x80070070 (disk full), content download failures.
Confirm: Check free space on C:; review CAS.log, ContentTransferManager.log.
Fix: Increase cache size:
PowerShell
UIResourceMgr = New-Object -ComObject UIResource.UIResourceMgr
$cache = $UIResourceMgr.GetCacheInfo()
$cache.Size = 10240 # MB
Clean old content, expand OS disk, move temp folders off system volume.

3) Wrong Boundary Group / DP selection

Symptom: Error 0x87D00692, 0x87D00607, content not found.
Confirm: LocationServices.log shows fallback to a remote DP; CAS.log shows “no content locations.”
Fix: Correct boundaries (add subnets/cidrs), set preferred DP, re‑distribute package, trigger Machine Policy and Scan Cycle.

4) WUA scan errors (e.g., 0x8024401c / 0x8024402c)

Symptom: Scan fails; client never evaluates updates.
Confirm: WUAHandler.log, WindowsUpdate.log (on newer OS use Get-WindowsUpdateLog).
Fix: Fix proxy/WSUS URL, allowlist SUP in firewall, reset WU components:
BAT
net stop wuauserv
net stop bits
del /s /q %windir%\SoftwareDistribution\*
net start bits
net start wuauserv

5) Superseded/expired updates in the SUG

Symptom: Deployed updates are “Not Required” or never install.
Confirm: In SCCM, check Supersedence column; UpdatesDeployment.log shows filtered out.
Fix: Update ADR filters to Required AND Not Superseded, regenerate SUG, redeploy.

6) SSU prerequisite missing on older OS

Symptom: “Update not applicable” (older platforms that don’t bundle SSU).
Confirm: CBS.log shows missing servicing stack level.
Fix: Install the Servicing Stack Update first, then the CU; for newer OS, ensure the single combined package is used.
Tip for interview: “On modern Windows 10/Server 2004+, the SSU is bundled with LCU; on older builds we stage SSU first.”

7) Maintenance window too short (0x87D00664 timeout)

Symptom: Updates download but don’t install within the window.
Confirm: UpdatesDeployment.log shows install start then deferral due to window end.
Fix: Extend the window, split large rollups, or pre‑cache content before the window.

8) Hash mismatch / corrupt DP content

Symptom: Clients fail to verify content hash.
Confirm: PkgXferMgr.log & Monitoring → Content Status show failures.
Fix: Validate package, clear DP content, and re‑distribute; if needed, ContentLibraryCleanup.exe on the DP.

9) Dual Scan / GPO conflicts (WSUS vs Windows Update)

Symptom: Servers talk to Microsoft Update instead of WSUS/SUP, or vice versa.
Confirm: WUAHandler.log shows service location; check GPOs: Do not allow update deferral policies to cause scans against WU.
Fix: Align GPOs to single authority (WSUS/SUP or WU), disable dual scan, and set the correct Intranet Microsoft update service location.

10) BITS/Network throttling

Symptom: Very slow downloads; timeout.
Confirm: DataTransferService.log shows throttling; network QoS policies in place.
Fix: Relax throttling windows, enable peer cache/BranchCache (if applicable), or stage content to local DP.

11) Third‑party updates certificate issue

Symptom: 3rd‑party patch deployment fails (e.g., Chrome/Java).
Confirm: SCUP/Partner catalog cert expired; client shows untrusted publisher.
Fix: Renew/import the WSUS signing certificate; re‑publish metadata; re‑sync.

12) EDR/AV blocking update installer

Symptom: Update download succeeds; install fails mid‑way.
Confirm: EDR console shows a block/quarantine event; Windows Event Log shows access denied on temp files.
Fix: Add temporary exclusions for the update process path; coordinate with SecOps.

13) CCM client health / WMI corruption

Symptom: Policy not applying; updates stuck “Unknown”.
Confirm: ccmrepair output; ClientIDManagerStartup.log, WMI query failures (wbemtest).
Fix: ccmrepair; if needed, rebuild WMI repository:
BAT
net stop winmgmt
winmgmt /salvagerepository
winmgmt /resetrepository

Reinstall client with ccmsetup.exe /mp:<MP> SMSSITECODE=<CODE>.

14) Time skew / TLS handshake failures to SUP

Symptom: Scan fails with SSL/TLS errors; WSUS/SUP uses HTTPS.
Confirm: Event logs show certificate or handshake issues; certutil -verify against SUP cert.
Fix: Correct NTP/time, validate certificate chain, ensure SCHANNEL protocols match server policy.

15) Windows Component Store corruption (CBS)

Symptom: CU install repeatedly fails with generic 0x800f081f/0x800f0922‑type errors.
Confirm: CBS.log, DISM finds corruption.
Fix:
BAT
dism /online /cleanup-image /restorehealth
sfc /scannow

Reboot; retry install.

16) Clustered workloads & CAU edge cases

Symptom: CU installs on one node but cluster roles fail to move.
Confirm: Failover Cluster Manager shows resource dependency issues; CAU logs show failures.
Fix: Drain roles manually, stop dependent services before install, patch nodes sequentially, confirm Cluster Aware Updating runbook.

17) CMG vs on‑prem DP pathing (hybrid)

Symptom: Internet‑based servers fail to download content from CMG or choose on‑prem DP they can’t reach.
Confirm: LocationServices.log shows content location over on‑prem; boundary groups missing Cloud entries.
Fix: Add Cloud DP/CMG to boundary groups; prefer cloud for internet clients; re‑evaluate policy.

18) Metered connection or NIC flagged as metered

Symptom: Update scan OK, download never starts.
Confirm: NIC shows metered; registry policy for “allow downloads on metered” not set.
Fix: Disable metered flag or enable policy to allow downloads on metered connections.

🔧 Quick triage cheat‑sheets you can quote

DNS quick checks

PowerShell

# Name resolution path

ipconfig /all

ipconfig /flushdns

ipconfig /displaydns

Resolve-DnsName <name> -Server <dnsIP> -Type A

Resolve-DnsName <ip> -Type PTR

# DFS referrals (if shares)

dfsutil /pktinfo

dfsutil /spcinfo

Updates quick checks (SCCM client)

PowerShell

# Trigger common cycles

Invoke-WmiMethod -Namespace root\ccm -Class SMS_Client -Name TriggerSchedule `

-ArgumentList '{00000000-0000-0000-0000-000000000021}' # Machine Policy Retrieval

Invoke-WmiMethod -Namespace root\ccm -Class SMS_Client -Name TriggerSchedule `

-ArgumentList '{00000000-0000-0000-0000-000000000113}' # Software Updates Scan

Invoke-WmiMethod -Namespace root\ccm -Class SMS_Client -Name TriggerSchedule `

-ArgumentList '{00000000-0000-0000-0000-000000000108}' # Software Updates Deployment Eval

# Rebuild Windows Update log (modern OS)

Get-WindowsUpdateLog

Key client logs: WUAHandler.log, UpdatesDeployment.log, UpdatesHandler.log, CAS.log, ContentTransferManager.log, DataTransferService.log, LocationServices.log.
Site logs: WSyncMgr.log, wcm.log, WCM.log, SUPSetup.log.

Tech-Gen