INE’s CCIE R&S v5 topology for EVE-NG

The last days I was working on adapting INE‘s lab topology, most specific the CCIE Routing and Switching v5 one, to be used in EVE-NG.

In my opinion, INE offers some of the best training materials for Cisco and Juniper certifications. Along certification training you can find in their All Access Pass Subscription valuable learning materials for Network Automation, Security and Traffic Analysis (like Wireshark).
By the way I’m not affiliated with nor this post is the result of some sponsorship from INE. I just wanted to have the possibility to use their materials on using the entire topology, including the Switches, in EVE-NG.

I’ve picked Cisco‘s vIOS L3 and L2 images to support the topology in EVE-NG. You can argue that vIOS is a bit unstable and lacks some features, that CSR1000v images are better when combined with real Cisco switches and so on. Yes yes, all these are quite right, but I’m not here to debate about the best way to create a topology, rather a simple and sustainable one which works even for low end devices with less resources (CPU, RAM). Is no secret that vIOS will use less resources than CSR1000v images.

It brings me great happiness to let you know that I’ve succeeded in adapting not only the topology (not that hard honestly), but also the initial configuration files. The challenge lies in the fact that vIOS L2 images are build to support Ethernet ports in group of four, resulting in a slight different naming convention.

If you’ll check INE’s CCIE R&S v5 topology, the Cisco switches are using the Port from 19 to 24 to interconnect. On switch SW1, Port 1 is used to bridge the switching part to the routing one. You cannot replicate this exact port configuration scheme using vIOS L2 images.

I was forced to come with an alternative scheme, to map the original interface to the virtual ones and to adapt the configuration files.

This is what I came with:

INE CCIE R&S v5 switches

The interface mapping is as follows:

Real Switches – vIOS-L2

Fa0/1  - Gi0/0 - SW1 only connection to bridge

Fa0/19 - Gi0/2
Fa0/20 - Gi0/3
Fa0/21 - Gi1/0
Fa0/22 - Gi1/1
Fa0/23 - Gi1/2
Fa0/24 - Gi1/3

For the Routers is easy, since the interfaces are almost the same:

CSR1000v – vIOS-L3

Gi1 - Gi0/1

Here is how the network topology looks like:
INE CCIR R&S v5 Topology

We have 10 Routers using vIOS-L3 and 4 Switches using vIOS-L2. The connections between routers and switches are facilitated by the Net bridge.
10 routers should be sufficient for most of the labs. However if you need more, just add nodes and connect them to the Net bridge using the Gi0/1 interface.

As said previously, the configuration files have been adapted to match the interfaces listed above. I’ve tried my best not to have any errors, I also did some testing, everything looks to be fine. Most probably you’ll notice some errors at the copy / paste, but these are just cosmetic and related mostly to some proprietary CSR1000v commands or management interface which is not needed in EVE-NG. If you encounter errors that are critical, please let me know and I’ll try to correct them.

If somebody from INE’s team reads this post (that would be something :)) and consider inappropriate to share the modified initial configuration files, please let me know and I’ll take them down. They are derived from the public available ones on the CCIE R&S v5 Topology Diagrams & Initial Configurations page and do not contain any workbook information or somehow else related to INE’s training materials.

Download files:

Happy labbing and let me know if you find these materials useful!

Cisco BGP soft-reconfiguration and received-routes relation

A while ago I received the following question:

“Why I’m not seeing the prefixes received from the BGP peer when using the show ip bgp neighbors x.x.x.x received-routes while the soft-reconfiguration inbound is not enabled?”

I must admit that I had to stop and think for a second before giving my response.

Simple BGP

For the above diagram I have a simple BGP configuration:

router bgp 65301
 bgp router-id
 bgp log-neighbor-changes
 neighbor remote-as 65302
 neighbor timers 5 15
 address-family ipv4
  network mask
  network mask
  network mask
  neighbor activate
router bgp 65302
 bgp log-neighbor-changes
 neighbor remote-as 65301
 neighbor timers 5 15

Focus is on the secondary router. I’m trying to see what prefixes I receive from my BGP neighbor, so I rapidly hit the following command:

R2#sh ip bgp neighbors received-routes
% Inbound soft reconfiguration not enabled on

OK, that’s not good. Am I missing the command? Let’s see:

R2#sh ip bgp neighbors ?
  advertised-routes  Display the routes advertised to a BGP neighbor
  dampened-routes    Display the dampened routes received from neighbor (eBGP
                     peers only)
  flap-statistics    Display flap statistics of the routes learned from
                     neighbor (eBGP peers only)
  paths              Display AS paths learned from neighbor
  policy             Display neighbor polices per address-family
  received           Display information received from a BGP neighbor
  received-routes    Display the received routes from neighbor
  routes             Display routes learned from neighbor
  |                  Output modifiers

-> received-routes – Display the received routes from neighbor

OK, I know the soft-reconfiguration inbound is not enabled, but what has this to do with the fact that the command is not showing me what routes I receive from BGP neighbor?

Let’s recall what “soft-reconfiguration inbound” command actually does.

BGP soft-reconfiguration inbound
*Cisco BGP-4 Command and Configuration Handbook

According to the above explanation, if you have an inbound policy (like a route-map) applied to a BGP neighbor and you change that policy, you need to clear the BGP session before it take effect. This is the procedure without having “soft-reconfiguration inbound” configured. I remember it like this and most of the network engineers out there remember this behavior associated with the “soft-reconfiguration inbound” command.

Still, I just want to see what routes I received from BGP neighbor and according with “sh ip bgp neighbors received-routes” description is the right command . I have no inbound policy on R2 for R1 BGP neighbor.

A less remembered fact about the “soft-reconfiguration inbound” command is that when added, the router begins to store updates from the specified neighbor. These updates are unmodified by any existing inbound policies so that the router can correctly apply the new policies when soft reconfiguration is triggered.

Where are these updates stored?

In the BGP Adj-RIB-in (Adjacent Routing Information Base, Incoming) table. So, what the “received-routes” command does actually is looking in the BGP Adj-RIB-in table for the received routes from the BGP neighbor. I consider that the “received-routes” command has an ambiguous explanation leading to confusion.

When “soft-reconfiguration inbound” is not present, the BGP router does not store anything in Adj-RIB-in. Rather it process the update and discard the Adj-RIB-in table, but not before adding the information in the Loc-RIB (Local Routing Information Base) table. Knowing these facts of course the BGP router returns an error when trying to check the received prefixes using the “received-routes” command.

To check actually what’s received from BGP peer and stored in the Loc-RIB (after being processed by inbound policies) use only the “routes” parameter in the command:

R2#sh ip bgp neighbors routes | b Net
     Network          Next Hop            Metric LocPrf Weight Path
 *>              0             0 65301 i
 *>              0             0 65301 i
 *>              0             0 65301 i

Total number of prefixes 3

-> routes – Display routes learned from neighbor

The output is what exists in the Loc-RIB table, after processed by the inbound policy.

Let me show you an example of the above explanation.

I’ll apply the “soft-reconfiguration inbound” first:

R2(config-router)#neighbor soft-reconfiguration inbound

Now I’ll check again the received routes:

R2#sh ip bgp neighbors received-routes  | b Net
     Network          Next Hop            Metric LocPrf Weight Path
 *>              0             0 65301 i
 *>              0             0 65301 i
 *>              0             0 65301 i

Total number of prefixes 3

OK, so I have three prefixes, reflected in the Adj-RIB-in table.
Checking next the Loc-RIB tables (so the routes installed after being processed by inbound policies):

R2#sh ip bgp neighbors routes | b Net
     Network          Next Hop            Metric LocPrf Weight Path
 *>              0             0 65301 i
 *>              0             0 65301 i
 *>              0             0 65301 i

Total number of prefixes 3

The Adj-RIB-in and Loc-RIB tables are identical.

Now, I’ll apply an inbound policy that will filter the prefix.

R2(config)#ip prefix-list LIST permit
R2(config)#route-map INBOUND deny 10
R2(config-route-map)#match ip address prefix-list LIST
R2(config-route-map)#route-map INBOUND permit 1000
R2(config-route-map)#router bgp 65302
R2(config-router)#neighbor route-map INBOUND in

OK, we have the “soft-reconfiguration inbound” in place, so the inbound policies should be applied automatically denying the prefix.

R2#sh ip bgp neighbors received-routes | b Net
     Network          Next Hop            Metric LocPrf Weight Path
 *>              0             0 65301 i
 *>              0             0 65301 i
 *              0             0 65301 i

The above output is what we receive from BGP peer. Notice that the prefix is still there, in the Adj-RIB-in table, as the inbound policies are not applied yet. The only visible change is the missing > sign (best).

R2#sh ip bgp neighbors routes | b Net
     Network          Next Hop            Metric LocPrf Weight Path
 *>              0             0 65301 i
 *>              0             0 65301 i

Now we can see that the inbound policy is working fine as the prefix is not installed in the Loc-RIB table. This is also the explanation why the > (best) sign was missing from the prefix in Adj-RIB-in.

I hope you understood the logic behind the confusion which these commands “received-routes” and “routes” and their explanation in IOS is creates.

Please let me know in Comments if you have any questions.

CCIE Home Lab, what to do when your router has too little Flash space for IOS

I already explained in an older post my home lab for CCIE preparation. My BB1-BB3 routers are Cisco 2600 series and the rest of R1-R6 are emulated with Dynamips. The only problem is that one of the C2600 has too little Flash space to hold the required IOS. Memory is sufficient, but Flash not.

The only workaround I have is to load the IOS image from a TFTP server. I will explain here my procedure, maybe it’s useful for somebody else out there.

First, I recently upgrade to Ubuntu 12.04 and for some reason the TFTPD (default tftp server) was not working properly. I found TFTPD-HPA to be a good alernative, so I did install it:

sudo apt-get install tftpd-hpa

After installation you may want to check /etc/default/tftpd-hpa. On my system it looks like this:

# /etc/default/tftpd-hpa

Next step is to get a IOS image and copy it under /var/lib/tftpboot. If you need a hint, I’m using c2600-adventerprisek9-mz.124-25d.bin which needs only a small amount of memory to be installed on the Cisco 2600 platform and it’s enough for testing.

Now we need to get the IOS image on the C2600 using TFTP. Depending on your topology used for CCIE exam practice, this can be done in different ways.

Currently I’m using the workbooks from Micronicstraining (Narbik’s workbooks, if this sounds more familiar). Previously I used the ones from Internetwork Expert. The idea is that topology is pretty similar and it looks something like this:

Narbik’s workbook topology

My problematic router is the BB3. Somehow I need that BB3 is communicating with my Ubuntu server, as simple as possible, without changing ethernet cables all the time.
You noticed int the above diagram that BB3 has an interface on the SW1 (Fa0/13) and SW1 has F0/1 connected to my Ubuntu server as explained in this post. What I need is to have Fa0/13 and Fa0/1 on the SW1 on the same VLAN for proper communication. Usually I just default the interface and then everything is fine.

On the Ubuntu box, I can have an IP address on the physical card (this will not influence in any way the Dynamips emulated router attached to this interface):

eth1      Link encap:Ethernet  HWaddr 00:e0:b6:06:a6:3b
          inet addr:  Bcast:  Mask:
          inet6 addr: fe80::2e0:b6ff:fe06:a63b/64 Scope:Link
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:64 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 B)  TX bytes:14100 (14.1 KB)

By default on the BB3 router I have an IOS image that can fit the Flash size (c2600-i-mz.123-26.bin) and in case that for some reasons the TFTP Server is not reachable, it will boot that image.

The BB3 startup-configuration looks like this:

interface FastEthernet0/0
 ip address
boot system tftp c2600-adventerprisek9-mz.124-25d.bin

What you have to remember:
1. Start your TFTP server and assure that it has the correct IP address on the interface where you will server IOS files
2. Start your switch (if you have one in between Cisco router and the TFTP server) and be sure that the interfaces are able to exchange packet (same VLAN, etc)
3. Start your Router

In case you did miss any of the above steps, you’ll see something like this:

%SYS-4-CONFIG_NEWER: Configuration from version 12.4 may not be correctly understood
 Slot is empty or does not support clock participate
 WIC slot is empty or does not support clock participate
%SYS-6-READ_BOOTFILE_FAIL: tftp:// File read failed -- Timed out.
 Hello from IFS_TYPE_ROM successful type-check
%SYS-6-BOOT_MESSAGES: Messages above this line are from the boot loader.
boot of "tftp:c2600-adventerprisek9-mz.124-25d.bin" using boot helper "flash:c2600-i-mz.123-26.bin" failed
error returned: File read failed -- Timed out
loadprog: error - on file open
boot: cannot load "tftp:c2600-adventerprisek9-mz.124-25d.bin"

and the router will boot your image stored locally on Flash.

Instead of doing all this work, which may generate some headache, I could just buy another router with enough Flash (and Memory). Currently I don’t want to make this investment, so I’ll stick with the above scenario.

[Twitter IT] Cisco Live 365 – Cornerstones of CCIE Success

Cisco Live 365 describe this as:

“Anthony Sequeira, CCIE, CCSI educates students on four key cornerstones for success in the journey to CCIE. These cornerstones include technical knowledge, study and lab strategies, proper mindset, and physical wellness.”

I can tell you it’s not essentially a technical knowledge session, and Anthony Sequeira mention this couple of times during presentation. Nevertheless this it’s damn good for your CCIE preparation and exam itself. What Anthony Sequeira does, he tries to “educate” the attendant behavior pre and during the exam so he or she won’t go crazy. If you have a Cisco Live 365 account (it’s free to subscribe) I would recommend this presentation.

[Infographic] The Journey to Cisco Certification Success

I found this great Infographic on Pinterest and I felt the need to share it though my blog. Even if not all information are 100% accurate of complete, it’s still a nice view that worth spending some minutes to check.