All networking labs

• Interface Administratively Down - beginner, 20 minutes, Routing

  Configure Interface Administratively Down.

• OSPF Single-Area - Bring Up 2 Routers - beginner, 20 minutes, Routing

  Restore or configure OSPF routing for the required networks.

• Static Routing - beginner, 20 minutes, Routing

  Provide static routing between the required internal networks.

• Static Routing - Hub with 3 Branches - beginner, 20 minutes, Routing

  Provide static routing between the required internal networks.

• Wrong Default Gateway - beginner, 20 minutes, Routing

  Configure Wrong Default Gateway.

• DNS - Stand Up an Internal Resolver - beginner, 20 minutes, Services

  Restore the required internal name-resolution service.

• DNS Service Cutover - beginner, 20 minutes, Services

  Point the internal service name to its replacement host.

• EIGRP - Bring Up 2 Routers - beginner, 20 minutes, Routing

  Restore or configure EIGRP routing for the required networks.

• Split One LAN Into Two VLANs - beginner, 15 minutes, Switching

  Separate engineering from sales on one switch, using VLANs alone.

• ACL Fundamentals - Block a Single Host #1 - intermediate, 20 minutes, Security

  Apply the required network access restriction.

• ACL: Block a Whole Subnet #1 - intermediate, 20 minutes, Security

  Apply the required network access restriction.

• ACL Fundamentals - Implicit Deny #1 - intermediate, 20 minutes, Security

  Apply the required network access restriction.

• Branch DNS Service - intermediate, 20 minutes, Services

  Resolve and reach a central DNS service from a branch.

• Department VLANs with Local DHCP - intermediate, 20 minutes, Services

  Deliver department VLAN membership and local DHCP leases.

• DHCP & NAT - intermediate, 20 minutes, Services

  Provide automatic addressing and shared Internet access.

• DHCP Pool #1 - intermediate, 20 minutes, Services

  Provide automatic addresses without using reserved infrastructure addresses.

• DHCP Scope Eats the Server Block - intermediate, 20 minutes, Services

  Clients lease fine - out of the block reserved for servers.

• DHCP Hands Out the Wrong Gateway - intermediate, 20 minutes, Services

  Clients lease an address but cannot reach anything beyond the segment.

• EIGRP - Fix R2 (3-Router Chain) - intermediate, 20 minutes, Routing

  Restore or configure EIGRP routing for the required networks.

• Segment the Guest Network - intermediate, 20 minutes, Security

  Configure Segment the Guest Network.

• Hub-and-Spoke Missing Routes - intermediate, 20 minutes, Routing

  Configure Hub-and-Spoke Missing Routes.

• Inter-VLAN Routing - intermediate, 20 minutes, Switching

  Configure Inter-VLAN Routing.

• OSPF Default Route (2 Routers) - intermediate, 20 minutes, Routing

  Advertise an Internet default route through the OSPF domain.

• OSPF Passive User LAN - intermediate, 20 minutes, Routing

  Advertise a user LAN while keeping it passive in OSPF.

• OSPF Single-Area - intermediate, 20 minutes, Routing

  Restore or configure OSPF routing for the required networks.

• NAT Overload (PAT) #4 - intermediate, 20 minutes, Services

  Give an internal network shared outbound Internet access.

• Publish Server Port Forwarding - intermediate, 20 minutes, Services

  Configure Publish Server Port Forwarding.

• Shared-Segment Wrong Next-Hop - intermediate, 20 minutes, Routing

  Configure Shared-Segment Wrong Next-Hop.

• Linux Router IP Forwarding - intermediate, 20 minutes, Routing

  Configure Linux Router IP Forwarding.

• One Server, Wrong Exit Interface - intermediate, 20 minutes, Routing

  One destination is unreachable from a single workstation.

• Static Routing - Full Mesh of 3 LANs - intermediate, 20 minutes, Routing

  Provide static routing between the required internal networks.

• The Route That Isn't There - intermediate, 20 minutes, Routing

  A configured static route that never reaches the routing table.

• Static Routing - Summarize 3 Branch LANs - intermediate, 20 minutes, Routing

  Provide static routing between the required internal networks.

• Trunk Missing a VLAN - intermediate, 20 minutes, Switching

  Configure Trunk Missing a VLAN.

• Access Port in the Wrong VLAN - intermediate, 20 minutes, Switching

  One workstation is isolated despite correct addressing.

• Allow Access to Wiki Replica - intermediate, 20 minutes, Security

  Configure Allow Access to Wiki Replica.

• Permit One Service, Not One Host - intermediate, 20 minutes, Security

  Narrow a host-level permit down to the one service it was meant to allow.

• BGP Customer LAN Advertisement - intermediate, 20 minutes, Routing

  Advertise the customer application LAN through BGP.

• BGP: Two-Router eBGP Session - intermediate, 20 minutes, Routing

  Establish the required external BGP route exchange.

• Slow, Not Broken - intermediate, 20 minutes, Routing

  Diagnose a link that is up, passing traffic, and unusable - then route around it.

• The Config Backup Server Everyone Can Reach - intermediate, 20 minutes, Security

  Restrict a file transfer service to the segment that is supposed to use it.

• IPv6 Static Routing Across Three Sites - intermediate, 20 minutes, Routing

  Join three IPv6 sites with static routes, and verify reachability end to end.

• The Patch Panel Labels Are Wrong - intermediate, 20 minutes, Routing

  Use LLDP to find the real topology, then fix routes written from the wrong one.

• The Protocol That Loses Your Subnet Masks - intermediate, 20 minutes, Routing

  RIP is running on both routers and the LANs still cannot reach each other.

• Overly Broad Firewall Rule - intermediate, 20 minutes, Security

  Monitoring system flags guest Wi-Fi reaching the payroll server

• Contractor Limited Access - intermediate, 20 minutes, Security

  Give the auditing contractor access to exactly one server, nothing else

• Audit IoT VLAN Internet Scope - intermediate, 20 minutes, Security

  Confirm the IoT VLAN really can only reach the firmware update service, nothing more

• Lock Down Management Access - intermediate, 20 minutes, Security

  Anyone on the office network can currently try to log into the core router — fix that

• Finance Subnet Default Deny - intermediate, 20 minutes, Security

  Stand up the new finance subnet default-deny from day one

• Egress Filter on the Records Server - advanced, 20 minutes, Security

  An outbound filter permits the wrong department and blocks the right one.

• ACL Stateful Return Traffic - advanced, 20 minutes, Security

  Apply the required network access restriction.

• The Firewall That Never Saw the Request - advanced, 20 minutes, Security

  Replies are dropped by a firewall that never saw the request.

• Traffic Leaves by the Backup Circuit - advanced, 20 minutes, Routing

  Everything is reachable - over the wrong circuit.

• eBGP Session Up, No Routes - advanced, 20 minutes, Routing

  An established eBGP session that exchanges no prefixes.

• BGP Transit Site Onboarding - advanced, 20 minutes, Routing

  Onboard a site through a two-hop eBGP transit path.

• DNS Round-Robin Backend Failure - advanced, 20 minutes, Services

  Restore the required internal name-resolution service.

• EIGRP Multi-Path - advanced, 20 minutes, Routing

  Restore or configure EIGRP routing for the required networks.

• EIGRP Multi-Path #1 - advanced, 20 minutes, Routing

  Restore or configure EIGRP routing for the required networks.

• Static Route Outranks OSPF - advanced, 20 minutes, Routing

  Traffic prefers a backup path even though OSPF learned the direct one.

• iBGP Route Learned but Never Installed - advanced, 20 minutes, Routing

  The prefix is in Core's BGP table but never reaches its routing table.

• Small Packets Fine, Large Packets Gone - advanced, 20 minutes, Routing

  A link that passes small packets and silently drops large ones.

• OSPF Area Mismatch on a New Link - advanced, 20 minutes, Routing

  Restore or configure OSPF routing for the required networks.

• OSPF Stuck in ExStart - advanced, 20 minutes, Routing

  An OSPF neighbour that never leaves ExStart.

• OSPF Multi-Area #1 - advanced, 20 minutes, Routing

  Restore or configure OSPF routing for the required networks.

• Selective Static Redistribution - advanced, 20 minutes, Routing

  Advertise one static route into OSPF while withholding another.

• Web Tier Bypasses App Tier - advanced, 20 minutes, Security

  Security review finds the web servers can talk directly to the database — they shouldn't be able to

• Overbroad Summary Route Blackhole - advanced, 20 minutes, Routing

  Configure Overbroad Summary Route Blackhole.

• Divested Business Firewall Separation - advanced, 20 minutes, Security

  Separate companies sharing a building must not share network access

• Fix Split-Horizon DNS - advanced, 20 minutes, Services

  Configure Fix Split-Horizon DNS.

• STP Root Bridge Elected Wrong - advanced, 20 minutes, Switching

  Configure STP Root Bridge Elected Wrong.

• Tagged Port, Untagged Host - advanced, 20 minutes, Switching

  A port in the correct VLAN that still passes no host traffic.