Real Work Practice

Ticket Simulation Labs: Troubleshoot Like Support

Certification labs teach configuration. Tickets teach behaviour: listen, isolate, verify, document and escalate cleanly.

# Ticket Template

FieldWhat I must write
User reportWhat the user says, without adding my own assumptions.
Business impactWho is affected and how urgent it is.
Initial checksPower, link, IP, gateway, DNS, routing, firewall, service status.
Commands usedExact commands and important output.
Root causeThe real reason, not just the symptom.
Fix and verificationWhat changed, how I proved it works, and what evidence I saved.
Escalation noteWhat to hand to Level 2/3 if I cannot fix it.

# First 12 Ticket Labs

T01 APIPA Address

Beginner

User has 169.254.x.x address and cannot access internet.

Check: DHCP, cable, switch port, adapter status.
Proof: before/after ipconfig, DHCP fix note.

T02 DNS Failure

Beginner

Website opens by IP address but not by name.

Check: nslookup, DNS server, cache, reachability.

T03 Wrong Gateway

Beginner

Local devices ping each other, but internet fails.

Check: IP, mask, gateway, route table.

T04 VLAN Port Mistake

CCNA

One department cannot reach its gateway after a desk move.

Check: show vlan brief, access port VLAN, patching.

T05 Trunk Missing VLAN

CCNA

VLAN works on one switch but not across another switch.

Check: show interfaces trunk, allowed VLANs, native VLAN.

T06 Duplicate IP

CCNA

Connection drops randomly after a new device was added.

Check: ARP table, DHCP leases, static IP conflict.

T07 Printer Not Reachable

Support

Users cannot print to a network printer.

Check: IP, ping, DNS name, port, VLAN, printer web page.

T08 VPN Connects, Apps Fail

Security

VPN says connected but internal application does not open.

Check: routes, DNS suffix, firewall, split tunnel, port test.

T09 Switch Port Err-disabled

CCNA

Desk port is dead after plugging in a device.

Check: port-security, BPDU guard, logs, recovery steps.

T10 Slow Network

Troubleshooting

User reports slow internet; no obvious outage.

Check: latency, packet loss, DNS time, Wi-Fi signal, bandwidth, duplex.

T11 Wi-Fi Connected, No Internet

Wireless

Laptop connects to Wi-Fi but cannot browse.

Check: DHCP, gateway, DNS, captive portal, AP isolation.

T12 DHCP Scope Full

Services

New users cannot obtain IP addresses during busy hours.

Check: DHCP leases, scope size, reservations, rogue devices.