Wednesday, June 25, 2014

One of my favorite actors, with some invaluable life advice. 

RIP Eli Wallach.

Tuesday, June 24, 2014

CCENT And CCNA Flash Card Practice Exam

It's nice to share, so share and Google +1 this exam! :) 


As always, my Flash Card questions give you no multiple choice answers.  (Neither will a Cisco router or switch!)

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Tease over.  Let's get the job done!


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1.  You have four routers on an OSPF broadcast network.  There are no issues with adjacencies or timers.  Once the network has converged, how many routers will have full adjacencies with all other routers on that segment?


2.  Of our EIGRP friends bandwidth, MTU, delay, and load, which ones figure into the default OSPF route calculation formula?


3.   Of the hello timer, dead timer, and stub flag setting, which must match in order for an OSPF adjacency to form?


4.  Here's the partial output of an important OSPF command.  Name the command.

Link ID         ADV Router      Age         Seq#       
172.12.13.1     172.12.13.1     1435        0x80000002 
172.12.123.2    172.12.123.2    1436        0x80000003

172.12.123.3    172.12.123.3    1436        0x80000003 


5.   Name the command that resulted in this output.  (Not all output shown, and this is an EXCELLENT troubleshooting command. Hint hint.)

Serial0 is up, line protocol is up
 Internet Address 172.12.123.1/24, Area 0
 Process ID 1, Router ID 172.12.13.1, Network Type NON_BROADCAST, Cost: 64
 Transmit Delay is 1 sec, State DR, Priority 1
 Designated Router (ID) 172.12.13.1, Interface address 172.12.123.1
 No backup designated router on this network
 Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5

   Hello due in 00:00:14


Let me bend your ear for a moment before we discuss the answers.
I'm only human.

(Really!)

I know it's really, really easy to let your studies drop during the summer.   It's even easier to put off studying for a new certification.

Please listen to me when I say....

Letting your studies come to a halt in the summer and losing your success momentum is the worst thing you can do.  

It's that much harder to get started again in September, because then it's really easy to say, "Well, I'll start in October", which becomes "Well, the holidays are here, so I'll start after the New Year...."

Suddenly it's freakin' 2015, and you've wasted six months of study time!

You have two and only two choices right now:

1.  Keep your studies going through the summer and get your certifications done.

2.  Quit studying, lose your momentum, and all of a sudden you're wondering where 2014 went.

To give you more incentive to keep your success momentum, I'm offering you the lowest prices EVER on my CCNA Video Boot Camp and CCNA Security Video Boot Camp.

Right now, you can earn your CCNA with me for just $33.

That's right.  $33.

Over 50,000 students are already in my courses on Udemy, and over 9300 of them are in this great CCNA course.

Follow these links and join us today - and keep rolling on your way to exam and real-world success!

We're also donating 20 meals to the Central Virginia FoodBank for every CCNA and CCNA Security signup in July!



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See you there! 

Let's check out the answers to today's free CCNA and CCENT practice exam....


1.  The only routers that will have a full adjacency to all other routers on the OSPF broadcast network are the DR and BDR.  The DROthers will form a 2-way adjacency with those routers.

Sounds odd?  It did to me, too.  Watch this video from my CCNA And CCENT Video Training channel on YouTube for a demo on live Cisco routers!





2.  The OSPF route calculation formula is Cost = Reference / Bandwidth, so that narrows it down to bandwidth! 


3.  The OSPF hello timer, dead timer, and stub flag setting must ALL match in order to form and maintain an OSPF adjacency.


4.  The command we ran to get that output was show ip ospf database.  


5.   That's the output of show ip ospf interface with the Serial0 option, which gave me info on that interface only.  That's a great command to use to check your OSPF Hello and Dead timers, the OSPF process ID in use, and many other important OSPF values.

Thanks for taking today's free exam!  I'll see you Wednesday with another one, and at least one new video!  


Chris B.



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Here's a new CCNP SWITCH practice exam for you!





Let's hit these flashcard questions hard, and when you're done here, be sure to use these additional free CCNP SWITCH tutorials to help you nail the exam and earn your CCNP!


No need to put your answers in the form of a question, but if you want to hear Alex's voice in your head, feel free!


1.  This command globally enables DHCP Snooping on a Cisco switch.



2.  The full interface-level command that enables DHCP Snooping on a particular interface and confirms the port is indeed trustworthy.



3.  When dealing with STP defaults, a port's path cost of 19 indicates you're working with this port speed.


4.  It's the default STP priority of a Cisco switch.


5.  Of loop guard, root guard, and port security, the Cisco switch security feature that can result in a port entering the "root-inconsistent" state.


Answers and today's video right after this important, time-sensitive offer!



Join over 50,000 students in my Video Boot Camps --


-- and earn your CCNP with me for $77!


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Get your CCNP with my $44 CCNP SWITCH Video Boot Camp!



And for a VERY limited time, use this link and banner to join my CCNP All-In-One Video Boot Camp for just $77.

You receive over 50 hours of my world-class CCNP instruction for just $77, and you can download the videos as well as stream them!




The answers to today's questions:


1.   The global command is ip dhcp snooping.


2.   The interface-level command we need is ip dhcp snooping trust.


3.   The default STP path cost of a Fast Ethernet port is 19.


4.   The default priority of a Cisco switch is 32678.


5.   A root guard violation will cause a port to go into root-inconsistent state.


Thanks for taking today's practice exam!  I'll see you on YouTube and Udemy!

Chris B.


My CCNP SWITCH Study Guide is one of the highest-rated networking books on Amazon --- thanks to you!

Don't have your copy yet?  Grab it right now - I guarantee it's the best 10 bucks you'll ever spend on your CCNP studies!

Tuesday, June 17, 2014

CCNA And CCNP In-Depth Lab:

Today: Advanced, real-world usage of the IP ROUTE command.


Like it?  Google +1 it. Got it?  Good!  : )  --  Chris B.

In an earlier CCNA and CCNP Command Discussion, we saw the fundamentals of the ip route command in action. Today, we'll see an often-overlooked option of this command that can serve you well in real-world networking...

... and it'll also reinforce an important Cisco routing concept or two. Let's get started!

In networking, we'll take as much redundancy as we can get. It's not enough to have one loop-free path from "A" to "B", we want a backup path in place so if the primary path goes down for any reason, the backup path can smoothly (we hope!) go into action.

(If you were waiting for the "but", it's on the way.)

But on occasion, networking can get just a bit complicated.  For example, today's network!



CCNA CCNP Floating Static Route Lab 1




Simple enough, right?  

Welll......

In real-world networking, not all connections are equal.  

I realize that's a Blinding Glimpse of the Obvious (BGO), but it's something books and other study guides tend to leave out.

Physically, R1 has three paths it can use to reach the 172.12.23.0 /24 network:

1.  Through the frame cloud and then through R2.

2.  Through the frame cloud and then through R3.

3.  Via the serial link S1 that leads to R3.

That's the good news.

However, the serial link that leads directly to R3 is so slow and/or unreliable that we can't run a routing protocol over it. It's so bad that the client is forbidding us from making this the primary path for R1 to reach 172.12.23.0 /24.  The slow path should only serve as the primary route in case the OSPF path is unavailable.

That's the bad news.

As a result, R1 has only the first two paths available to reach 172.12.23.0 /24....

R1#show ip route

< code table removed for clarity >

Gateway of last resort is not set

     172.12.0.0/24 is subnetted, 3 subnets
C       172.12.13.0 is directly connected, Serial1

O    172.12.23.0 [110/74] via 172.12.123.3, 17:13:51, Serial0

                  [110/74] via 172.12.123.2, 17:13:51, Serial0


C       172.12.123.0 is directly connected, Serial0

... and if something happens to Serial0, R1 then has NO paths to 172.12.23.0 /24.  

R1(config)#int s0
R1(config-if)#shut

1d00h: %OSPF-5-ADJCHG: Process 1, Nbr 172.12.123.3 on Serial0 from 2WAY to DOWN,
 Neighbor Down: Interface down or detached

1d00h: %OSPF-5-ADJCHG: Process 1, Nbr 172.12.123.2 on Serial0 from 2WAY to DOWN,
 Neighbor Down: Interface down or detached

1d00h: %LINK-5-CHANGED: Interface Serial0, changed state to administratively down

1d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to down

R1#show ip route

Gateway of last resort is not set

     172.12.0.0/24 is subnetted, 1 subnets
C       172.12.13.0 is directly connected, Serial1


No worries, though.  We'll use the ip route command to create a static route to the 172.12.23.0 /24 network, we'll then have two routes in the routing table for R1 to use, and then all will be well.

Or... WILL it?

Let's find out!  I've reopened Serial0, and the original routes to 172.12.23.0 /24 are back in place:

     172.12.0.0/24 is subnetted, 3 subnets
C       172.12.13.0 is directly connected, Serial1
O       172.12.23.0 [110/74] via 172.12.123.3, 00:00:28, Serial0
                    [110/74] via 172.12.123.2, 00:00:28, Serial0

C       172.12.123.0 is directly connected, Serial0

Let's add our static route!

R1(config)#ip route 172.12.23.0 255.255.255.0 172.12.13.3

That should get our new route into the routing table...

R1#show ip route

Gateway of last resort is not set

     172.12.0.0/24 is subnetted, 3 subnets
C       172.12.13.0 is directly connected, Serial1
S       172.12.23.0 [1/0] via 172.12.13.3

C       172.12.123.0 is directly connected, Serial0

... and the new static route is in place.   That's the good news.

However, our OSPF routes to that same destination are gone.

And you know that's bad news.

What the heck happened here?

We'll figure that out right after this important message about your professional and personal future -- and how you can help the hungry while you build that future!

I know it's really, really easy to let your studies drop during the summer.   It's even easier to put off studying for a new certification.

Letting your studies come to a halt in the summer and losting your success momentum is the worst thing you can do.  

It's that much harder to get started again in September, because then it's really easy to say, "Well, I'll start in October", which becomes "Well, the holidays are here, so I'll start after the New Year...."

Before you know it, you've wasted six months of study time - and it wouldn't have taken you that long to get the certification in the first place!

You have two choices:

1.  Keep your studies going through the summer and get your certifications done.

2.  Quit studying, lose your momentum, and all of a sudden you're wondering where 2014 went.

To give you more incentive to keep your success momentum, I'm offering you the lowest prices EVER on my CCNA Video Boot Camp and CCNP All-In-One Video Boot Camp.

Right now, you can earn your CCNA with me for just $33.

My CCNP All-In-One course is only $77, and I guarantee it's the best investment you'll ever make in your CCNP studies.

Over 50,000 students are already in my courses on Udemy. Follow these links and join us today - and keep rolling on your way to exam and real-world success!


We're also donating 20 meals to the Central Virginia FoodBank for every CCNA and CCNA Security signup, and 100 meals for every CCNP signup!



Only $33 With This Link!






Join For Only $33 With This Exclusive Link!





Over 50 hours of world-class training for the ROUTE, TSHOOT, and SWITCH exams!




See you there! 

Let's get back to our lab, and answer that one burning question... WHERE DID OUR OSPF ROUTES GO?

Sorry for the yelling.  But we gotta figure this out -- and it goes back to a very important Cisco routing concept, administrative distance.

Right now, R1 is hearing about the exact same route (172.12.23.0 /24) from two different sources:

1.  A locally written IP ROUTE statement

2.  The dynamic routing protocol OSPF

R1 has to decide which source to pay attention to -- that is, which source is the most believable.  That's where admin distance (AD) comes in.  

AD is a measure of a route source's trustworthiness.  Both of these sources are trustworthy, but one has to be considered "more trustworthy", and that will be the source with the lowest AD.

OSPF routes have an AD of 110, as seen in an earlier routing table. The first number in the brackets seen in the routing table entries is always the AD, and the second is the metric for that route.

O       172.12.23.0 [110/74] via 172.12.123.3, 00:00:28, Serial0
                    [110/74] via 172.12.123.2, 00:00:28, Serial0


Static routes have a much lower AD, and if the static route is written as we wrote it here, it will always have a lower AD than any dynamic routing protocol.  That's why the static route took the place of the OSPF routes.

However, in this case, we didn't want that to happen.  The link the static route uses was described as "slow and/or unreliable", so we sure don't want that to be our primary link.

Also, the client told us to use the Serial1 link only as a backup.

One solution to this issue is to create a floating static route, and it's just about as easy as writing a regular static route.  Before we get started, let's remove the current static route.

R1(config)#no ip route 172.12.23.0 255.255.255.0 172.12.13.3

As a result, the OSPF routes reappear in the routing table.

     172.12.0.0/24 is subnetted, 3 subnets
C       172.12.13.0 is directly connected, Serial1
O       172.12.23.0 [110/74] via 172.12.123.3, 00:00:47, Serial0
                    [110/74] via 172.12.123.2, 00:00:47, Serial0

C       172.12.123.0 is directly connected, Serial0

Before we configure our floating static route, let's talk for a moment about what the heck a floating static route even is.  What's the "floating" bit?

A floating static route is odd -- you don't see it in the routing table, but it's in the config, and when you need it, it'll appear.

Sounds like some super-complicated CCIE-level deal, right?  Wrong!  You'll write a floating static route almost exactly as you'll write a regular static route. The only difference is at the very end of the command.

R1(config)#ip route 172.12.23.0 255.255.255.0 172.12.13.3 ?
  <1-255>    Distance metric for this route
  name       Specify name of the next hop
  permanent  permanent route
  tag        Set tag for this route
  <cr>

Success with floating static routes is all about the "distance metric for this route".  That's not the best description of administrative distance I've ever seen, but that's what this value is.  When you specify a value here, you're changing the AD of the static route.

To make the route "float", just set that AD to a value higher than that of the routing protocol(s) in use on this router.  Since OSPF's AD is 110, we'll just go one higher and set the AD of this static route to 111.

R1(config)#ip route 172.12.23.0 255.255.255.0 172.12.13.3 111

As a result of that little change, the static route will appear in the config...

ip route 172.12.23.0 255.255.255.0 172.12.13.3 111

... but the OSPF routes remain in the IP routing table.

     172.12.0.0/24 is subnetted, 3 subnets
C       172.12.13.0 is directly connected, Serial1
O       172.12.23.0 [110/74] via 172.12.123.3, 00:12:26, Serial0
                    [110/74] via 172.12.123.2, 00:12:26, Serial0
C       172.12.123.0 is directly connected, Serial0

The floating static route is ready to step in at a moment's notice!  Let's shut Serial0 down and then check the routing table.

R1(config)#int s0
R1(config-if)#shut

Gateway of last resort is not set

     172.12.0.0/24 is subnetted, 2 subnets
C       172.12.13.0 is directly connected, Serial1
S       172.12.23.0 [111/0] via 172.12.13.3
R1#
R1#
R1#ping 172.12.23.3

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.12.23.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 36/36/36 ms

Best of all, we have connectivity to the 172.12.23.0 /24 network!

When Serial0 comes back up and the OSPF adjacencies do the same, the router will make the AD decision again and put the OSPF routes back into the routing table and remove the static route at the same time.

1d01h: %OSPF-5-ADJCHG: Process 1, Nbr 172.12.123.3 on Serial0 from LOADING to FULL, Loading Done
1d01h: %OSPF-5-ADJCHG: Process 1, Nbr 172.12.123.2 on Serial0 from LOADING to FULL, Loading Done

Gateway of last resort is not set

     172.12.0.0/24 is subnetted, 3 subnets
C       172.12.13.0 is directly connected, Serial1
O       172.12.23.0 [110/74] via 172.12.123.3, 00:00:08, Serial0
                    [110/74] via 172.12.123.2, 00:00:08, Serial0
C       172.12.123.0 is directly connected, Serial0

That's all there is to a floating static route!

Thanks for reading today's tutorial, and for sharing it out - you're the only advertising The Bryant Advantage has!

Be sure to read these other tutorials, and sign up for these Video Boot Camps on Udemy!  They're all me and 100% free!




My Free Video Boot Camps on Udemy:

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See you there!

Chris B.

Wednesday, June 11, 2014

Hey Bulldogs!

Thanks for the great response to the new CCNA / CCNP Command References I've been posting!

I'll have a new one for you on Friday - right now, enjoy these videos from my YouTube Cisco Certification Video Training channel.   

And while you're here, take just a moment to join these free CCNA, CCNP, and CCNA Security courses of mine on Udemy.  I'll see you there!

Free CCNA Video Boot Camp: OSPF

Free CCNA Security Course: CCP (And More!)

Free CCNP ROUTE Course: Advanced OSPF



Chris B.


Here's a CCNA and CCNP QuizLab for you on VTP:





Whether you're working on your CCENT, CCNA, or CCNP, these IP Version 6 Compression Drills will help you get the job done and whip the exam!






Finally, let's play a little "What's This Command?" 




Sunday, June 08, 2014

CCNA And CCNP In-Depth Lab:

The Three (Three?) ADs Of EIGRP



Your only cost for this huge CCNA and CCNP tutorial is a share or a Google +1.  Thanks!   -- Chris B.

A few basics of admin distance before we get EIGRP-specific:

The administrative distance of a route doesn't really have anything to do with "distance".  It's actually a measurement of the believability of a route source. 

The lower the AD, the more believable the source is.


The AD range is 0 - 255, with 255 indicating an untrustworthy source.

Simple enough, right?  Right!  

But.... (and you knew that was coming) .... there are some additional details that go along with ADs that we need to know for our CCNA and CCNP exams as well as avoiding confusion when working with real-world networks.

Take the admin distances of EIGRP routes, for example.  And yes, I said "distances", because there are multiple EIGRP admin distances -- and not just the two you might already know about.

Let's take a look at the two most common EIGRP admin distances in action on Cisco routers, and review some other important EIGRP concepts along the way.

In this lab, R1 and R2 have an EIGRP adjacency over the 172.12.123.0 /24 network, and all routes we add to the network will be added to R1.  Autosummarization is disabled on both routers.

R1 has two loopbacks, 1.1.1.1 /32 and 2.2.2.2 /32, that are not shown, as they're not part of the lab -- yet. 



CCNA And CCNP EIGRP Lab

We'll add one loopback to EIGRP on R1 via the network command.   The all-zeroes wildcard mask means the single address indicated in the network command will be advertised by EIGRP.

R1(config)#router eigrp 100

R1(config-router)#network 1.1.1.1 0.0.0.0

Does the route appear in R2's EIGRP route table?

R2#show ip route eigrp

     1.0.0.0/32 is subnetted, 1 subnets
D       1.1.1.1 [90/2297856] via 172.12.123.1, 00:00:06, Serial0

Yes, and it appears with the router table code "D", indicating an internal EIGRP route.   That route type has an admin distance of 90, as seen in the brackets.   The first number in the bracket is always the AD, and the second is the metric for the route.

We'll demo the second route type by using the redistribute connected and default-metric commands in R1's EIGRP config. EIGRP requires a seed metric for successful redistribution.  For you CCNPs-to-be, I'll use IOS Help to show each value you need for that command. This is good stuff for future CCNAs and CCENTs as well, but don't expect to see this command on your exams.

R1(config)#router eigrp 100

R1(config-router)#default-metric ?
  <1-4294967295>  Bandwidth in Kbits per second

R1(config-router)#default-metric 1500 ?

  <0-4294967295>  Delay metric, in 10 microsecond units

R1(config-router)#default-metric 1500 10 ?

  <0-255>  Reliability metric where 255 is 100% reliable

R1(config-router)#default-metric 1500 10 255 ?

  <1-255>  Effective bandwidth metric (Loading) where 255 is 100% loaded

R1(config-router)#default-metric 1500 10 255 1 ?

  <1-4294967295>  Maximum Transmission Unit metric of the path

R1(config-router)#default-metric 1500 10 255 1 1544


R1(config-router)#redistribute connected

What does R2's routing table show us now?

R2#show ip route eigrp
     1.0.0.0/32 is subnetted, 1 subnets
D       1.1.1.1 [90/2297856] via 172.12.123.1, 00:06:52, Serial0
     2.0.0.0/32 is subnetted, 1 subnets

D EX    2.2.2.2 [170/2297856] via 172.12.123.1, 00:02:30, Serial0

The new route is in the table and is marked "D EX".  That indicates an EIGRP external route, and the AD of that route type is 170. 

Note the first route still has an AD of 90, even though it is a connected route on R1, which would fall under the "redistribute connected" command we just configured.

When a route is added to EIGRP via both the network command and the redistribute connected command, the network command takes precedence and the route will be an EIGRP internal route.

Those are the two main admin distances of EIGRP routes, and the ADs you'll see most often in real-world networking.

But I did mention a third, didn't I?  

We'll run a lab on the other AD values in just a moment -- but let me address another concern for a moment.

I know it's really, really easy to let your studies drop during the summer.   It's even easier to put off studying for a new certification.

Letting your studies come to a halt in the summer and losting your success momentum is the worst thing you can do.  

It's that much harder to get started again in September, because then it's really easy to say, "Well, I'll start in October", which becomes "Well, the holidays are here, so I'll start after the New Year...."

Before you know it, you've wasted six months of study time - and it wouldn't have taken you that long to get the certification in the first place!

You have two choices:

1.  Keep your studies going through the summer and get your certifications done.

2.  Quit studying, lose your momentum, and all of a sudden you're wondering where 2014 went.

To give you more incentive to keep your success momentum, I'm offering you the lowest prices EVER on my CCNA Video Boot Camp and CCNP All-In-One Video Boot Camp.

Right now, you can earn your CCNA with me for just $33.

My CCNP All-In-One course is only $77, and I guarantee it's the best investment you'll ever make in your CCNP studies.

Over 50,000 students are already in my courses on Udemy. Follow these links and join us today - and keep rolling on your way to exam and real-world success!




Only $33 With This Link!







Over 50 hours of world-class training for the ROUTE, TSHOOT, and SWITCH exams!




See you there!   Right now, let's head back to the lab!

We can go beyond the default EIGRP admin distances of 90 and 170 and set the distance of these route types manually with the distance command.  

Please note: Even if you're familiar with this command, read the rest of this tutorial. There's a little trick with this command that a lot of network admins don't know about.

R2 has two routes in its EIGRP table right now, one with an AD of 90 and another with an AD of 170.

R2#show ip route eigrp
     1.0.0.0/32 is subnetted, 1 subnets
D       1.1.1.1 [90/2297856] via 172.12.123.1, 00:00:15, Serial0
     2.0.0.0/32 is subnetted, 1 subnets
D EX    2.2.2.2 [170/2297856] via 172.12.123.1, 00:00:15, Serial0

Let's say we need to make these routes even more trustworthy, and lower the AD for each route type to 50.

There are two things we have to know to make this happen:

1.  What command do we need? 

2.  On which router or routers do we need this command?

We know the answer to #1 already -- but what about #2? Should we change the AD on R1, R2, or both?

Let's start with R1, along with a little IOS Help.

R1(config)#router eigrp 100
R1(config-router)#distance ?
  <1-255>  Administrative distance
  eigrp    IP-EIGRP distance

R1(config-router)#distance eigrp ?

  <1-255>  Distance for internal routes

R1(config-router)#distance eigrp 50 ?

  <1-255>  Distance for external routes

R1(config-router)#distance eigrp 50 50 ?

  <cr>


R1(config-router)#distance eigrp 50 50

17:15:08: %DUAL-5-NBRCHANGE: IP-EIGRP 100: Neighbor 172.12.123.2 (Serial0) is down: route configuration changed
17:15:08: %DUAL-5-NBRCHANGE: IP-EIGRP 100: Neighbor 172.12.123.3 (Serial0) is down: route configuration changed
R1#
17:15:26: %DUAL-5-NBRCHANGE: IP-EIGRP 100: Neighbor 172.12.123.3 (Serial0) is up: new adjacency

Two very important notes regarding this config:

Using the distance command will result in your local EIGRP adjacencies coming down.  If nothing else has been changed, they should come back up quickly, but this isn't something you want to do on a production network at a busy time of day.  In this example, the adjacencies came back in about 18 seconds.

Don't use the numeric option with the distance command in this situation. To change the admin distance for all your EIGRP routes, use distance eigrp. (The numeric option has a LOT of other mandatory values you'll need to configure.)

Now -- what effect did this have on the EIGRP routes on R2?

None whatsoever.

R2#show ip route eigrp
     1.0.0.0/32 is subnetted, 1 subnets
D       1.1.1.1 [90/2297856] via 172.12.123.1, 00:00:01, Serial0
     2.0.0.0/32 is subnetted, 1 subnets
D EX    2.2.2.2 [170/2297856] via 172.12.123.1, 00:00:01, Serial0

Administrative distance is locally significant only.  When you change the AD of a route, that change isn't advertised.  It only takes effect locally.

Let's remove the distance command from R1 and add it to R2's config.

R1(config)#router eigrp 100

R1(config-router)#no distance eigrp 50 50

R2(config)#router eigrp 100


R2(config-router)#distance eigrp 50 50

The result on R2:

R2#show ip route eigrp
     1.0.0.0/32 is subnetted, 1 subnets
D       1.1.1.1 [50/2297856] via 172.12.123.1, 00:00:04, Serial0
     2.0.0.0/32 is subnetted, 1 subnets

D EX    2.2.2.2 [50/2297856] via 172.12.123.1, 00:00:04, Serial0

Ta da!  The AD of both EIGRP route types on R2 is now 50!

Two more important notes concerning this command:

The network command is an "all or nothing" command.  You can't specify a specific EIGRP internal route for an AD change while leaving the other internal routes untouched.  Same for the external routes.

While you don't have to change both ADs, you do have to specify both in the command.  Let's say we wanted to set the AD of EIGRP internal routes to 100 while leaving the external route AD at 170.  Here's how we do that:

R2(config-router)#distance eigrp ?
  <1-255>  Distance for internal routes

R2(config-router)#distance eigrp 100 ?

  <1-255>  Distance for external routes

R2(config-router)#distance eigrp 100 170


R2#show ip route eigrp

     1.0.0.0/32 is subnetted, 1 subnets
D       1.1.1.1 [100/2297856] via 172.12.123.1, 00:01:55, Serial0

     2.0.0.0/32 is subnetted, 1 subnets
D EX    2.2.2.2 [170/2297856] via 172.12.123.1, 00:01:55, Serial0

A lot going on with a simple one-word command, eh?  : ) 

Thanks for reading today's Cisco Command Discussion.  Right now, be sure to read these other important discussions, and I'll see you Monday -- and in my Video Boot Camps!

Chris B.

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