First, the essential ideas
- Static network route
- A manually configured route for a destination subnet. It supplies a local forwarding instruction, not a route automatically installed on every other router.
- Next-hop-only route
- A static route naming the next router's IP address. IOS must resolve that address to a usable output interface.
- Exit-interface route
- A static route naming the local output interface without a next-hop address. On Ethernet this can cause ARP for individual destinations and reliance on proxy ARP.
- Fully specified route
- A static route containing both the local output interface and the adjacent next-hop address. It makes the intended Ethernet forwarding relationship explicit.
- ARP and proxy ARP
- ARP finds an IPv4 neighbor's Ethernet address. Proxy ARP is a router answering on behalf of another destination; it can hide an inappropriate interface-only route.
- Recursive resolution
- A routing lookup used to determine how to reach a configured next hop. A route line alone does not establish that the intended neighbor or service is alive.
- Source and return route
- The source is the address from which a packet is sent. A reply needs a route back to that source; choosing a different ping source can expose a missing reverse route.
- Loopback
- A software interface with an address that the router owns. Here loopbacks are explicit source and destination endpoints, not networks full of unseen PCs.
- Mask and route scope
- A mask defines the destination range of a route. A /24 network route differs from a /32 host route, a /0 default or a higher-distance floating backup.
- Configuration versus operation
- Running configuration records intended commands. The routing table records selected entries. ARP and traffic tests add further evidence about actual forwarding.
Draw the request and the reply before configuring either route. A router-generated ping often uses its outgoing interface as the source by default; that can hide a missing route to another source subnet. This lesson names the loopback source explicitly so the test exercises both planned routes.
See the idea
The request and reply need different routes
A forward static route does not create the return route on the far router.
Send the request
R1 routes the request through R2 to its local 203.0.113.1 loopback.
What this model leaves out: Logical endpoint-and-route model, not a captured exchange. Loopbacks terminate traffic on the routers; no additional PCs or server networks are implied.
Full visual explanation and references
R1's source loopback sends through the transit to R2's loopback. The reply targets R1's loopback network and needs R2's separate reverse route.
Logical endpoint-and-route model, not a captured exchange. Loopbacks terminate traffic on the routers; no additional PCs or server networks are implied.
- Send the request
R1 routes the request through R2 to its local 203.0.113.1 loopback.
www.cisco.com - Route the reply
R2 needs 198.51.100.0/24 to return to the explicit source loopback.
www.cisco.com - Check both directions
Removing only R2's reverse route can break the exchange while transit reachability remains.
www.cisco.com
One idea at a time
Start with something familiar.
Write R1 Loopback0 198.51.100.1 and R2 Loopback0 203.0.113.1 at opposite sides of the page. Between them place only the 192.0.2.0/30 transit. Mark the address that each router must reach to return a reply.
Why learn this?
A successful ping from a router's transit address can give false confidence that all remote networks work. Specifying the source tests the actual reverse-route requirement instead of whichever source the router happens to choose.
An everyday comparison
Two offices can each know how to send a parcel to the other. Giving directions to only one office does not guarantee that a reply can find its way back.
What happens in a network
Each static route is a local instruction for one direction. The source written on the request determines the destination that the return route must cover.
Where the comparison stopsRouting is not postal delivery: ARP, interface state and prefix selection still determine forwarding. This analogy cannot promise delivery or diagnose a filter.
Follow one worked example
- Address the transit before adding remote routes.
R1 and R2 occupy the usable .1 and .2 addresses of 192.0.2.0/30.
Why: A next-hop instruction is meaningful only when the local router has a usable way to reach that neighbor.
- Add the two opposite network routes.
R1 needs 203.0.113.0/24 via R2; R2 needs 198.51.100.0/24 via R1.
Why: The request and reply have different destinations and therefore require different routing entries.
- Hold the ping source constant.
Test R2's loopback using R1 Loopback0 as the source, remove R2's reverse route and repeat.
Why: A fixed source makes the observed failure relate to the intended return-route dependency.
Your first small task
On paper, a ping leaves R1 with source 198.51.100.1 and destination 203.0.113.1. Write the reply's source and destination, then identify the remote prefix R2 needs.
Show a hint
Reverse the packet addresses, not the static command's mask. Each router evaluates the reply destination independently.
Check the expected result
The reply originates at 203.0.113.1 and targets 198.51.100.1, so R2 needs a route covering 198.51.100.0/24 in this lab.
Pause and explain it in your own words
Why might a default-source ping still work after R2's reverse /24 is removed?
Show a hint
The outgoing interface address is in the transit subnet both routers already know.
Show the explanation
R1 may source that ping from 192.0.2.1. R2 has a directly connected route to the transit /30, so it can reply without a route to 198.51.100.0/24. The loopback-sourced test exercises the missing remote return path.
Short answer
What should you understand today?
An IPv4 static route tells one router how to forward toward a destination prefix. On Ethernet, specifying the neighbor address, and often the exit interface too, avoids treating every remote destination as directly attached. Verify the installed route, the immediate neighbor and the route back to the packet's actual source.
Before you begin
Learning targets
- Complete route-table interpretation and longest-prefix selection.
- Use a fresh isolated CML 2.10 IOSv 15.9M pair, not the altered Day 30 project.
- Understand /24 and /30 masks; the exact endpoints and return path are supplied below.
- Configure a valid IPv4 network prefix and directly adjacent next hop.
- Compare next-hop-only, exit-interface-only and fully specified forms.
- Verify configured, installed and forwarding state separately.
- Use a fixed source to expose a missing return route.
- Restore only the removed route and repeat both-direction tests.
Words you will meet
Open a word when you need its meaning. You do not need to memorize the whole list before reading.
Static network route
A manually configured route for a destination subnet. It supplies a local forwarding instruction, not a route automatically installed on every other router.
Next-hop-only route
A static route naming the next router's IP address. IOS must resolve that address to a usable output interface.
Exit-interface route
A static route naming the local output interface without a next-hop address. On Ethernet this can cause ARP for individual destinations and reliance on proxy ARP.
Fully specified route
A static route containing both the local output interface and the adjacent next-hop address. It makes the intended Ethernet forwarding relationship explicit.
ARP and proxy ARP
ARP finds an IPv4 neighbor's Ethernet address. Proxy ARP is a router answering on behalf of another destination; it can hide an inappropriate interface-only route.
Recursive resolution
A routing lookup used to determine how to reach a configured next hop. A route line alone does not establish that the intended neighbor or service is alive.
Source and return route
The source is the address from which a packet is sent. A reply needs a route back to that source; choosing a different ping source can expose a missing reverse route.
Loopback
A software interface with an address that the router owns. Here loopbacks are explicit source and destination endpoints, not networks full of unseen PCs.
Mask and route scope
A mask defines the destination range of a route. A /24 network route differs from a /32 host route, a /0 default or a higher-distance floating backup.
Configuration versus operation
Running configuration records intended commands. The routing table records selected entries. ARP and traffic tests add further evidence about actual forwarding.
A static route is a local destination instruction
The IOS command ip route takes a destination network, mask and forwarding information. It is entered in global configuration mode and affects only that router. The destination must be a valid prefix for the chosen mask, not a host address incorrectly paired with a network mask. A static route does not assign an interface address, create a remote network or tell another router how to return traffic.
- Write destination, mask and next hop in separate worksheet columns.
- An accepted command still needs installed-route and traffic verification.
Compare three forms before choosing one
Next-hop-only syntax names the neighbor address and lets the router resolve the output interface. A fully specified route adds the local output interface, which is useful on Ethernet and makes the intended adjacency clear. An exit-interface-only route identifies no neighbor. That form is appropriate on a true point-to-point serial interface in the comparison example, but can cause Ethernet to resolve many remote destinations as though they were attached. A cable directly between two routers does not change Ethernet's multiaccess forwarding semantics.
- Use the local exit interface name, not the peer's port name.
- Do not depend on proxy ARP to make an unsuitable Ethernet recipe appear correct.
Verify route eligibility and neighbor resolution separately
A route may remain in running configuration while its intended next hop is unresolved or its interface is unavailable. Conversely, an installed route can point to a next hop whose Ethernet neighbor cannot actually be reached. Check interface state, the connected transit prefix, the destination-specific route and ARP evidence. Avoid clearing all ARP or routing state as a first response; doing so destroys useful context and can affect unrelated traffic.
- Configured, installed and reachable are three different claims.
- A next-hop-only route can resolve unexpectedly through another route in more complex designs.
The reply follows its own routing lookup
Each direction is routed independently. A request to R2's loopback can arrive successfully even when R2 has no path to the source loopback. Ping's failure then does not prove the forward route is wrong. A source-qualified ping is useful because it holds the return destination constant. The lab's two routes are exact network routes, not broad defaults, so deleting the reverse /24 has a visible and explainable effect.
- Inspect the reply destination explicitly.
- Do not replace a missing exact route with an unexamined default just to make one test pass.
Scope the route types across the sequence
A network route covers a subnet, a host route covers one address, and a default covers otherwise unmatched destinations. A floating static uses a higher AD than a preferred route for the same prefix and becomes eligible when that preferred route is absent. This chapter configures network routes and diagnoses their bidirectional dependency. Day 32 performs default, host and floating exercises, and Day 33 supplies the IPv6 route-type counterpart.
- Do not mark both-stack static routing complete from one IPv4 exercise.
- A floating backup is an installation preference, not automatic detection of every remote outage.
Choose an exact inverse and a meaningful retest
Before introducing the fault, copy the working R2 route into the private worksheet and write its exact restoration command. Remove only that route after baseline success. Preserve the forward lookup, transit test and failed fixed-source exchange. Restore the same reverse route and repeat both loopback-to-loopback tests. Do not erase configurations, reload nodes or reset the entire interface to recover a one-line change.
- Rollback restores the known state; it is not a broad cleanup guess.
- No independent review, image QA or runtime success is implied by static content validation.
Real-world walkthrough
The router ping passed, but the source subnet could not return
In a hypothetical branch, an operator tests a remote loopback from the router and gets replies, then concludes the remote route is complete. A later test using the branch loopback as source fails. The first test used the transit interface source, which the far router already knew as connected; the branch loopback network lacked a reverse route.
- Record the source and destination of both tests instead of comparing only the word ping.
- Verify the outgoing route to the remote loopback still selects the intended transit neighbor.
- On the far router, look up the branch loopback source prefix and identify its missing reverse route.
- Restore the authorized exact reverse network route and leave the forward route unchanged.
- Retest with the fixed source in both directions, then explain why the earlier transit-sourced success was narrower evidence.
Guided GNS3 lab
Build both routes, then remove only the reply path
Configure IPv4 network routes between explicit loopback endpoints, convert one to fully specified Ethernet syntax, observe a missing reverse route and restore it. These instructions predict behavior; no router was executed during authoring.
Addressing plan
| Device | Interface | Address | Purpose |
|---|---|---|---|
| R1 | Gi0/0 | 192.0.2.1/30 | Transit toward R2 |
| R2 | Gi0/0 | 192.0.2.2/30 | Transit toward R1 |
| R1 | Loopback0 | 198.51.100.1/24 | Fixed request source and reply destination |
| R2 | Loopback0 | 203.0.113.1/24 | Remote test destination and reverse-test source |
Set up the lab
- Use Cisco Modeling Labs 2.10 with its legally entitled bundled IOSv 15.9M reference image. Record the complete show version release; do not export that image to GNS3. No paid API is involved.
- Create fresh nodes and only the listed links. No External Connector, NAT node, bridge, public uplink or production network is permitted. Leave console access independent of the test data links.
- IOSv examples use GigabitEthernet0/0 and GigabitEthernet0/1. Confirm those exact ports in the workbench and show ip interface brief before configuring; if your image differs, document an explicit port substitution first.
- Decline the initial configuration dialog on a new authorized node, press Enter to reach the prompt, then use enable. Do not bypass unknown credentials. All displayed expected results are predictions, not author runtime.
- Without an entitled compatible image, complete the address and route-selection worksheet only. Mark command execution, packet forwarding and recovery unmeasured.
Map the first router
In the isolated CML workbench, select R1, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Record release and verify the single Gi0/0 cable before configuring any address.
enable
show version
show ip interface briefWhat each command means
enable- Enter authorized privileged EXEC mode to inspect this named router.
show version- Record the exact IOSv release for compatibility and evidence.
show ip interface brief- Confirm Gi0/0 is the mapped transit interface and record starting state.
- What you should see
- The named fresh node and its expected port are identified.
- Why this step matters
- This creates a reliable device and interface boundary before any manual route is added.
Address R1's transit and source
In the isolated CML workbench, select R1, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Configure the exact /30 transit and /24 software source; no default route is needed.
enable
configure terminal
interface GigabitEthernet0/0
ip address 192.0.2.1 255.255.255.252
no shutdown
exit
interface Loopback0
ip address 198.51.100.1 255.255.255.0
endWhat each command means
enable- Enter authorized privileged EXEC mode; this does not change the network configuration.
configure terminal- Enter global configuration mode on this named router; accepted changes affect its running state.
interface GigabitEthernet0/0- Select R1's local cable toward R2.
ip address 192.0.2.1 255.255.255.252- Assign the .1 transit address with /30 mask.
no shutdown- Enable the selected transit interface.
exit- Return to global configuration to select the software interface.
interface Loopback0- Create the stable source endpoint on R1.
ip address 198.51.100.1 255.255.255.0- Assign the source loopback in the 198.51.100.0/24 network.
end- Return to privileged EXEC; this neither saves nor reverses accepted configuration changes.
- What you should see
- R1 owns the transit and source addresses; the transit becomes usable when R2 is ready.
- Why this step matters
- A loopback source makes the reverse route necessary instead of relying only on the directly connected transit.
Address R2's transit and destination
In the isolated CML workbench, select R2, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Use the opposite transit address and the distinct destination network.
enable
configure terminal
interface GigabitEthernet0/0
ip address 192.0.2.2 255.255.255.252
no shutdown
exit
interface Loopback0
ip address 203.0.113.1 255.255.255.0
endWhat each command means
enable- Enter authorized privileged EXEC mode; this does not change the network configuration.
configure terminal- Enter global configuration mode on this named router; accepted changes affect its running state.
interface GigabitEthernet0/0- Select R2's local cable toward R1.
ip address 192.0.2.2 255.255.255.252- Assign the .2 neighbor address in the same /30.
no shutdown- Enable R2's transit interface.
exit- Return to global configuration before creating the loopback.
interface Loopback0- Create R2's software destination endpoint.
ip address 203.0.113.1 255.255.255.0- Assign the destination loopback in the 203.0.113.0/24 network.
end- Return to privileged EXEC; this neither saves nor reverses accepted configuration changes.
- What you should see
- Both transit endpoints and loopbacks should be present; actual state must be inspected.
- Why this step matters
- The nonoverlapping address plan makes each direction's routing requirement unambiguous.
Add R1's next-hop network route
In the isolated CML workbench, select R1, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Add the forward network route in next-hop-only form first.
enable
configure terminal
ip route 203.0.113.0 255.255.255.0 192.0.2.2
endWhat each command means
enable- Enter authorized privileged EXEC mode; this does not change the network configuration.
configure terminal- Enter global configuration mode on this named router; accepted changes affect its running state.
ip route 203.0.113.0 255.255.255.0 192.0.2.2- Route the remote /24 through R2's adjacent transit IP; IOS resolves its local exit.
end- Return to privileged EXEC; this neither saves nor reverses accepted configuration changes.
- What you should see
- The route should install through Gi0/0 if the transit is usable.
- Why this step matters
- This is a complete next-hop form, not an interface address or an instruction automatically copied to R2.
Add R2's fully specified return route
In the isolated CML workbench, select R2, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Provide the reply path to R1's source loopback using both the local interface and neighbor.
enable
configure terminal
ip route 198.51.100.0 255.255.255.0 GigabitEthernet0/0 192.0.2.1
endWhat each command means
enable- Enter authorized privileged EXEC mode; this does not change the network configuration.
configure terminal- Enter global configuration mode on this named router; accepted changes affect its running state.
ip route 198.51.100.0 255.255.255.0 GigabitEthernet0/0 192.0.2.1- Route the source /24 through R2's Gi0/0 to adjacent R1; this is the fully specified form.
end- Return to privileged EXEC; this neither saves nor reverses accepted configuration changes.
- What you should see
- The reverse network route should appear when R2's transit is up.
- Why this step matters
- The response has a different destination from the request and needs its own route.
Verify the fixed-source baseline
In the isolated CML workbench, select R1, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Record all observations before any deliberate fault; repeat initial probes if neighbor discovery is still settling.
enable
show ip route 203.0.113.1
show ip arp
ping 203.0.113.1 source 198.51.100.1What each command means
enable- Enter authorized privileged EXEC mode to inspect this named router.
show ip route 203.0.113.1- Check the selected forward prefix and next hop.
show ip arp- Inspect immediate IPv4 neighbor resolution on the transit.
ping 203.0.113.1 source 198.51.100.1- Test R2's loopback with R1's loopback as explicit source, exercising the reverse /24.
- What you should see
- Expect the remote /24 via .2 and replies when both routes and interfaces work.
- Why this step matters
- A transit-sourced ping would not test the same return dependency, so preserve the source explicitly.
Make the forward Ethernet route explicit
In the isolated CML workbench, select R1, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Replace only R1's route form, keeping its destination and next-hop intent unchanged.
enable
configure terminal
no ip route 203.0.113.0 255.255.255.0 192.0.2.2
ip route 203.0.113.0 255.255.255.0 GigabitEthernet0/0 192.0.2.2
endWhat each command means
enable- Enter authorized privileged EXEC mode; this does not change the network configuration.
configure terminal- Enter global configuration mode on this named router; accepted changes affect its running state.
no ip route 203.0.113.0 255.255.255.0 192.0.2.2- Remove the original next-hop-only route before adding its explicit replacement.
ip route 203.0.113.0 255.255.255.0 GigabitEthernet0/0 192.0.2.2- Add the same destination via the local Gi0/0 and adjacent R2 address.
end- Return to privileged EXEC; this neither saves nor reverses accepted configuration changes.
- What you should see
- The same forwarding path should remain available after the brief replacement.
- Why this step matters
- This demonstrates the syntax difference while avoiding an interface-only Ethernet dependency on proxy ARP.
Confirm replacement and reverse baseline
In the isolated CML workbench, select R2, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Check the return route and test from the opposite loopback before removing it.
enable
show ip route 198.51.100.1
ping 198.51.100.1 source 203.0.113.1What each command means
enable- Enter authorized privileged EXEC mode to inspect this named router.
show ip route 198.51.100.1- Confirm the reverse /24 selects R1 on Gi0/0.
ping 198.51.100.1 source 203.0.113.1- Test R1's loopback with R2's loopback as source, exercising both network routes.
- What you should see
- Expect a complete reverse lookup and replies with the fully specified pair.
- Why this step matters
- This confirms both directions before attributing a later failure to the deliberate missing return route.
Remove only the return network route
In the isolated CML workbench, select R2, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Preserve the exact line in notes; leave all interfaces and R1's route unchanged.
enable
configure terminal
no ip route 198.51.100.0 255.255.255.0 GigabitEthernet0/0 192.0.2.1
endWhat each command means
enable- Enter authorized privileged EXEC mode; this does not change the network configuration.
configure terminal- Enter global configuration mode on this named router; accepted changes affect its running state.
no ip route 198.51.100.0 255.255.255.0 GigabitEthernet0/0 192.0.2.1- Delete only the documented reverse /24 route from R2.
end- Return to privileged EXEC; this neither saves nor reverses accepted configuration changes.
- What you should see
- R2 should no longer have a remote route to R1's loopback network.
- Why this step matters
- A single removed reverse dependency creates a meaningful fault while the forward route and transit remain available.
Compare transit and source-aware failure
In the isolated CML workbench, select R1, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Use the same target and source as the original test; record the difference from transit reachability.
enable
ping 192.0.2.2
show ip route 203.0.113.1
ping 203.0.113.1 source 198.51.100.1What each command means
enable- Enter authorized privileged EXEC mode to inspect this named router.
ping 192.0.2.2- Test the directly connected neighbor, whose reply does not need the missing remote /24.
show ip route 203.0.113.1- Confirm the forward route is still installed through R2.
ping 203.0.113.1 source 198.51.100.1- Repeat the original loopback exchange; R2 lacks the route needed for the reply.
- What you should see
- Expect the transit test to work and the loopback-sourced exchange to fail; retain actual output.
- Why this step matters
- The comparison shows why a working next hop is not evidence of a complete return path.
Restore the recorded reverse route
In the isolated CML workbench, select R2, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. Recreate only the exact removed entry, without adding a default route or resetting the node.
enable
configure terminal
ip route 198.51.100.0 255.255.255.0 GigabitEthernet0/0 192.0.2.1
endWhat each command means
enable- Enter authorized privileged EXEC mode; this does not change the network configuration.
configure terminal- Enter global configuration mode on this named router; accepted changes affect its running state.
ip route 198.51.100.0 255.255.255.0 GigabitEthernet0/0 192.0.2.1- Restore the intended reverse /24 through the original local interface and next hop.
end- Return to privileged EXEC; this neither saves nor reverses accepted configuration changes.
- What you should see
- The return route should reinstall and become usable again.
- Why this step matters
- The smallest documented inverse makes restoration attributable to the missing route rather than to an unrelated reset.
Repeat the original exchange
In the isolated CML workbench, select R1, open its Console tab and connect before typing. Start at > or #; use end first if a prior task left configuration mode. After restoration, compare the selected route and the exact fixed-source test with baseline.
enable
show ip route 203.0.113.1
ping 203.0.113.1 source 198.51.100.1What each command means
enable- Enter authorized privileged EXEC mode to inspect this named router.
show ip route 203.0.113.1- Confirm the forward /24 remains correctly installed.
ping 203.0.113.1 source 198.51.100.1- Repeat the original end-to-end loopback exchange after R2's route restoration.
- What you should see
- Expect recovery of the same exchange; record any discrepancy before stopping nodes.
- Why this step matters
- Only a matching retest closes the fault experiment; accepted configuration syntax alone is insufficient.
Verify
- Verify the two /24 prefixes are distinct from the connected transit /30.
- Compare the next-hop-only and fully specified R1 command forms without claiming a serial interface was executed.
- Record the fixed source with every loopback ping and explain its reverse prefix.
- Retain transit success, unchanged forward route, missing return route and restoration evidence.
Troubleshoot
- If IOS rejects a prefix, check that the destination network matches the mask; do not use a host value with a network mask accidentally.
- If the configured route is absent, inspect the output interface and next-hop resolution before changing distance.
- If a default-source ping works during the fault, identify its transit source; repeat the specified loopback-source test.
- If a route appears but traffic fails, examine neighbor and reply-path evidence rather than assuming installation proves reachability.
GNS3 does not provide Cisco images. Use software only when the applicable license or entitlement permits that environment. Do not share or redistribute image files. Cisco Modeling Labs is the official alternative; its reference images are licensed for use within CML unless separately licensed. A paper exercise needs no image, but does not establish hands-on competence. Virtual routers do not reproduce physical radios, PoE delivery, hardware forwarding rates or failover timing.
- Leave both documented fully specified network routes restored before stopping the project.
- Retain configuration and observed outputs privately; no startup-save or reboot test is claimed.
Practice set
Answer before you reveal
01What does the first address in ip route identify?
The subsequent mask defines that destination range. The next-hop field names a forwarding neighbor, so swapping these meanings changes the route.
02Why prefer an explicit neighbor on Ethernet?
An interface-only Ethernet route may trigger ARP for individual remote destinations and rely on proxy ARP. This is not the same as a true point-to-point serial link.
03Does adding R1's route create R2's return route?
Replies are new packets whose destination is the request's source. R2 independently needs a route covering that source.
04Why are loopbacks used as endpoints?
Their networks are remote across the transit, so a source-qualified exchange requires both network routes. They do not represent a hidden LAN of clients.
05What is a fully specified route?
It makes the intended Ethernet adjacency explicit but does not independently confirm the neighbor's liveness or the final service.
06What part of the exam static-routing objective remains?
This chapter's IPv4 network-route exercise is deliberately scoped. One successful test cannot establish mastery of every route type in both stacks.
Knowledge check
Quiz: prove the reasoning
Keep these
Technical takeaways
- A static route is local forwarding intent for a destination prefix.
- Specify an adjacent next hop on Ethernet.
- A fixed ping source exposes a specific reverse-route requirement.
- Inspect route installation and neighbor state separately.
- Restore only the documented fault and repeat the original exchange.
- Today's network-route lab is partial coverage of the full two-stack route-type objective.