Author: Calin

Calin is a network engineer, with more than 20 years of experience in designing, installing, troubleshooting, and maintaining large enterprise WAN and LAN networks.

[Twitter IT]: Cisco ONE OpenFlow / SDN

I just upgraded to WP 3.4 and apparently you can now embed tweets in your posts. I will do this from time to time, when there is something that really capture my interest. I will add the [Twitter IT] prefix to this posts. IT in this case is not coming from Information and Technology, but from my short form of Interesting Tweet.

As this feature was just launched and I found a nice article thanks to Mr. Ivan Pepelnjak, his article will hahonor to be the first tweet added on my blog.

 

 

 

Juniper, first steps after power-on the device

As you know from my previous posts, I’m trying to find time to gain some Juniper knowledge. During this “quest” I will add here some basic things about how to start working with Juniper devices. For now I know only the basics of Juniper configuration, but I hope that soon you’ll find here some more challenging scenarios.

I have a basic topology that you’ll find below. The scenario is already prepare to have some tasks which suppose integration between Juniper and Cisco environment.

Let’s assume that I did power on the two boxes J1 and J2 and now I’m connected to J1 through a console cable. After the boot sequence I’m left with something like this:

Tue Jun 12 11:46:06 UTC 2012
 
Amnesiac (ttyd0)
 
login:

All platforms running the Junos OS have only the root user configured by default, without any password. Let’s introduce that username and see what’s happening:

login: root
Password:
 
--- JUNOS 9.4R2.9 built 2009-03-25 07:50:02 UTC
root@%

What I have now in front is actually the shell of the FreeBSD OS. JunOS is based on the FreeBSD OS. If you ever interacted with a Linux based system, then you can run here specific linux commands. For example:

root@% ls
.snap           boot            jail            modules         sbin
COPYRIGHT       config          kernel          opt             staging
altconfig       data            libexec         packages        tmp
altroot         dev             mfs             proc            usr
bin             etc             mnt             root            var
root@% 
root@% 
root@% 
root@% ps u
USER   PID %CPU %MEM   VSZ   RSS  TT  STAT STARTED      TIME COMMAND
root  1153  0.0  0.2  1492   936  v0  Is+  11:46AM   0:00.02 /usr/libexec/getty
root   941  0.0  0.4  2636  2176  d0- S    11:46AM   0:00.14 /usr/sbin/eventd -
root  1264  0.0  0.2  1676  1252  d0  Is   11:50AM   0:00.05 login [pam] (login
root  1265  0.0  0.5  3872  2744  d0  S    11:51AM   0:00.21 -csh (csh)
root  1289  0.0  0.2  1612   996  d0  R+   11:54AM   0:00.01 ps u

OK, you got my point. To get from the FreeBSD shell to JunOS CLI, you need to enter the following:

root@% cli
root>

What you see now is the Operational Mode. In this mode the user can run basic and troubleshooting commands (like traceroute, ping…). You can get a list of commands using the ? (question mark):

root> ?
Possible completions:
  clear                Clear information in the system
  configure            Manipulate software configuration information
  file                 Perform file operations
  help                 Provide help information
  monitor              Show real-time debugging information
  mtrace               Trace multicast path from source to receiver
  op                   Invoke an operation script
  ping                 Ping remote target
  quit                 Exit the management session
  request              Make system-level requests
  restart              Restart software process
  set                  Set CLI properties, date/time, craft interface message
  show                 Show system information
  ssh                  Start secure shell on another host
  start                Start shell
  telnet               Telnet to another host
  test                 Perform diagnostic debugging
  traceroute           Trace route to remote host

If you want to compare the Operational Mode is somehow like Privilege level 1 under Cisco CLI. Still I have the feeling that Operational Mode offer a wider area of commands and more powerful than Cisco CLI Privilege level 1. I may be mistaken.

All platforms running the Junos OS come with a factory-default configuration. All factory-default configurations
allow access using the root account without any password. Nevertheless to activate a configuration you have first to set the password root password.Factory-default configurations can vary from one platform family to another or even between the different models
within the same platform family.
My default configuration looks like:

root> show configuration 
version 9.4R2.9;
system {
    syslog {
        user * {
            any emergency;
        }
        file messages {
            any notice;
            authorization info;
        }
        file interactive-commands {
            interactive-commands any;
        }
    }
}

I this first post my target is to set the hostname of the Juniper devices. To accomplish this step, I need to go first into configuration mode:

root> configure 
Entering configuration mode
The configuration has been changed but not committed
 
[edit]
root#

and then set the hostname:

root# set system host-name J1 
 
[edit]

If I look at the system prompt, it still shows root#, so it doesn’t quite seems to work. This is because I have to commit to activate the configuration:

root# commit 
[edit]
  'system'
    Missing mandatory statement: 'root-authentication'
error: commit failed: (missing statements)
 
[edit]
root#

Well, this didn’t work as expected. The most important thing that I learned when I started with Juniper is that before I can activate any configuration (commit) I need to set the password for the root user:

root# set system root-authentication plain-text-password              
New password:
Retype new password:
 
[edit]
root#

Let me try to commit one more time, after setting the root password:

root# commit 
commit complete
 
[edit]
root@J1#

You can see that the prompt did change into root@HOSTNAME# (in my case this is root@J1#). If you look again to the system configuration. I will exist the Configuration Mode and have another look at my config file:

root@J1> show configuration 
## Last commit: 2012-06-12 12:38:22 UTC by root
version 9.4R2.9;
system {
    host-name J1;
    root-authentication {
        encrypted-password "$1$DKpYj/Nd$TVFTars5T2.oM3y5eyp520"; ## SECRET-DATA
    }
    syslog {
        user * {
            any emergency;
        }
        file messages {
            any notice;
            authorization info;
        }
        file interactive-commands {
            interactive-commands any;
        }
    }
}
 
root@J1>

The host-name and root password appears now in the active configuration.

That’s it for today. Until next post, I will add the basic configuration for J2 and the Cisco, so I can go to basic interface configuration and connectivity check.


4 years since I registered FirstDigest.com

It has been 4 years since I did register the FirstDigest.com domain and I want to mark this on the blog timeline. Nevertheless, the first tech post will arrive on this blog only on November 2008 as first I had different plans for this domain name. Those of you who were curious enough to read the About page knows already the domain story.

Maybe it sounds stupid, but I would like to tell Happy Birthday FirstDigest.com.

The experience with my first Juniper certification

Last week I got my first Juniper certification, JNCIA-Junos, and I’m pretty excited about it. I had to start with this exam, which is somehow equivalent to CCNA,  for two reasons:

– it’s mandatory for all other Juniper exams
– as I start with a new vendor technology I need to get a good understanding of how Junos is working and how this CLI is different from Cisco one

Maybe you are curious why I wanted to go with another certification vendor than Cisco. Well, I felt the need to do something different, but still related to networking technology. I’m not thinking to move away from Cisco, as this is still my strong point, but I don’t want my mind to get used to think only “Cisco style”. If I may say like this, I want to “think  out of the box”. I went with Juniper as I was always curious about their products and the way they handle routing protocols, configuration, network interconnections and so on…

I must say it, the preparation and exam experience, was a very pleasant one. First of all, after registration, on the Juniper website, I got access to their Learning Portal from where I could download two books in PDF format, free of charge.  I already have the necessary networking fundamentals knowledge, so these two books were enough to prepare for this exam. If you are a beginner, there is another eLearning course available on the same Juniper Learning Portal called “Networking Fundamentals” which is also free of charge. I checked some chapters from this course and I was surprised how nice and clear the explanation was. Beginners can easy understand and learn the basic concepts.

The theory was fine, but I wanted to have some hands on experience, so I start looking on Internet about some cheap solutions to prepare. I was lucky enough to get two boxes with Junos on them. After connecting them, I was able to start with the basic configuration and ended configuring IGP, BGP, filtering, route manipulation, etc. I also established some connections between Cisco and Juniper and configure inter-vendor routing protocols IGP and BGP. That was fun and I will add in future some “how-to” on my blog.

Next, on the Juniper Learning Portal, any certification candidate can take a Pre-assessment exam. If you pass, you will get a voucher which offer you 50% discount from the exam price. A nice welcome gift!

Without breaking the agreement, I think I may say that the exam was “to the point” with clear questions expecting clear answers. No room for tricky interpretations of the questions, so if you did your lessons you will pass for sure.

On and on, it was a nice experience which did offer me an appreciated break from CCIE preparation. Depending on the available time, I think I will continue with JNCIS-ENT.

I have to mention only one ugly point during my entire experience with this Juniper certification. Those of you who follow me on Twitter or LinkedIN already know what I’m talking about. I had to attend this exam three times and not because I failed, but because the first two times, the testing center was thinking that my time worth nothing. Long story short, 1st time they said that there is an update ongoing and they cannot held exams. After rescheduling with help of Prometric, at the time and date suggested by the testing center, I went for the 2nd attempt just to find out that the testing center was closed and they did cancel (?!) all exams without any information. Finally, 3rd time I did book with another testing center. In the past I used this testing center for Cisco certifications. As expected the things went smooth this time. I’m not blaming Juniper or Prometric for the first two experiences, but nevertheless I’m expecting at least that they will notify the testing center about this unacceptable behavior.

Finally, my blog will remain mainly focused on Cisco, but I will also add some articles about Juniper / Junos in form of beginners how-to. I hope my articles will become more complex as I will gain more Juniper knowledge and my idea is to develop some scenarios which involve Cisco and Juniper mix environment.

If you have questions please use the comment form, but please don’t ask questions that I cannot respond to (ex. questions from exam).


[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.