Cisco Nexus 7000 upgrade to 8Gb

When upgrading a Nexus 7000 to NX-OS version 5.2 (using more than 1 VDC) or to NX-OS v6+, Cisco claims the need to upgrade the system memory to 8Gb. Note I have run on v5.2 using only 4Gb per SUP using 2 VDCs and it has worked just fine, but I should mention that the […]

Symmetric and Asymmetric Algorithms – Basic Differences


Symmetric uses only one key for both encryption and decryption. Sender and receiver share the same shared secret to transfer data securely. Algorithms include DES, 3DES, AES, IDEA, RC2/4/5/6, and Blowfish. Also referred to as "secret key" encryption.

DES - 56bit keys
3DES - 112bit and 168bit keys
AES - 128bit, 192bit, and 256bit keys
IDEA (International Data Encryption Alogrithm) - 128bit keys
RC2 - 40bit and 64bit keys
RC4 - 1bit to 256bit keys
RC5 - 0bit to 2040bit keys
RC6 - 128bit, 192bit, and 256bit keys
Blowfish - 32bit to 448bit keys


Asymmetric uses one key for encryption and another key for decryption referred to as public key infrastructure encryption. Key lengths generally ranging from 512 to 4096bits.

Example of asymmetric encryption RSA,EIGamal, Eliptical Curves, and Diffie Hellman

Netapp CNA Link Redundancy with a Single Nexus Switch

I ran into a configuration recently where I had a Netapp storage array with the UTA cards installed, so there two CNA ports on each filer for a total of 4 ports. However, instead of a dual-switch design, there was only a single Nexus 5000, and therefore, no vPC configuration. I needed to achieve some level of redundancy on an interface level, but ran into some problems which I’ll discuss.

My certification journey (J-Net)

This blog has also been published to the Juniper J-Net community portal

In 2005, when I was 18 years old, I finished high school I already knew what I wanted to do. I wanted to start a career in IT! The only thing I didn’t know was in what direction I wanted to go. So, I did a little bit of everything. The first important decision I took was to only finish high school and start working without going to university. I figured that, with enough dedication and focus, 4-5 years of work experience added with the right technical certifications would get me further in the IT world than a degree would get me. After 6 years I think I can say that it definitely worked for me!

 

Servers and Programming

I started with passing exams and getting my MCSE on Windows 2003. I had a few small companies where I was managing all IT systems. The largest one was my dad’s company where I was managing 4 servers, 10 workstation and 20 mobile devices (yes even in 2006 we had a custom developed Windows Mobile 5 application and all engineers were carrying smartphones). I was co-developing the custom Continue reading

Op script : all in one command

I've scheduled to write a post regarding Junos load balancing but I must carry out more tests before writing it. So I decided to post my code of a troubleshooting 'op' script which allows to display in one command all protocols related information of...

Op script : all in one command

I've scheduled to write a post regarding Junos load balancing but I must carry out more tests before writing it. So I decided to post my code of a troubleshooting 'op' script which allows to display in one command all protocols related information of...

Common EAP Methods


Challenge and Response methods

  • EAP-MD5: Uses MD5 based challenge and reponse for authentication
  •  EAP-GTC: Generic Token and OTP authentication

Certifcate based methods

  • EAP-TLS: Uses X509v3 OKI certificates and TLS mechanism for authentication

Tunneling Methods

  • PEAP: Tunnels over EAP types in an encrypted tunned, much like web-based SSL
  • EAP FAST: Tunneling method designed to require no certificates for deployment
Note: This is not a comprehensive list.

802.1x Roles


Role of the 802.1x Client Software

  • Supplicant is responsible for initiating on authenication sessions with the authenticator
  • Supplicant software can be included in the operating system or you can install a third party supplicant

Role of 802.1x Authenticator

  • The authenticator is refered to as the NAD (Network Access Device) such as a switch, WLAN controller, firewall, etc..
  • The supplicant is challenged by the authenicator, the supplicant enters credentials and the NAD passes credentitals to the authentication server. The authenticator also enforces policies on each 802.1x port.

Role of the 802.1x Authentication Server

  • Performs Authentication, Authorization and Accounting
  • Validates the authentication credentials of the supplicants that are forwarded by the NAD
  • Policy look-up based on the supplicant idenitiy and group affiliation and passes the policy to the NAD. This can be the for of DACL (Downloadable ACL) or VLAN assignment
  • An authentication server for Cisco can include Cisco ISE or Cisco ACS

Role of the Dirctory Server in 802.1x

  • Cisco ISE supports 
    • local user database (does not scale)
    • Supports Active Directory
    • LDAP
    • RSA Tokens
    • RSA Secure ID
    • Certificate

Omnigraffle Stencil for Cisco Nexus

I am a MAC user and I have been looking but could not find a OmniGraffle Stencil with the Cisco Nexus icons, so I ended making one. I have also submitted the stencil to Graffletopia.com Feel free to download it and from Graffletopia or Mediashare:Cisco Nexus Hardware.gstencil.zipFiled under: General info

NX-OS Virtual PortChannels and Best Practices

Port-Channels, are a way of aggregating physical links together so that you can load balance traffic over each link to increase bandwidth, and create more redundancy. You might commonly see this configured between two switches, as shown below: Each link works together to form a logical, loop-free interface. These are relatively commonplace, and in this scenario highly useful because it prohibits spanning tree from blocking one of these ports, allowing the switch to utilize each link.

BYOD

BYOD (Bring Your Own Device) - There are security concerns when allowing employees, customers, and business partners to bring in there own device and plug it into the corporate network. Cisco has consolidated its ACS and NAC platform into a new product called ISE (Identity Services Engine). This new platform centralizes and simplifies the administration and empowers security groups the ability to make automated decisions. Have a look at the video below:



Terry: this one is for you as I am sure this challenge has come up many times.


Additional Interface Statistics

Sometimes you may need to have some additional interface statistics, for example the amount of packets per range of sizes. You can use netflow to collect some stats like these. But if you don't have netflow on all your router interfaces or for troubleshooting...

Additional Interface Statistics

Sometimes you may need to have some additional interface statistics, for example the amount of packets per range of sizes. You can use netflow to collect some stats like these. But if you don't have netflow on all your router interfaces or for troubleshooting...

Some Out-of-Box NetApp Tweak Suggestions

It’s interesting to me to see the differences in infrastructure products as it pertains to out of the box, or default configuration. Take for instance, the relationship between a firewall and a switch. Your average firewall is configured “closed”, meaning that if you want to allow anything, you have to explicitly allow that certain type of traffic. If you do not, it is not allowed. A switch, on the other hand, is configured to be functional above all, out of the box.

MX960 and E-SCB: Full Power

The aim of this post is to provide the detailed procedure for upgrading the Switch Control Boards (SCB) of an MX960 chassis in order to overcome some limitations of the old SCB that are : - Unable to use the full load of the 16x10GE card and to keep fabric...

Cisco and their inconsistencies

Cisco is known for the inconsistencies between platforms and different IOS versions. I came across another that was rather annoying. Now between linecards. Trying to configuring the following standard sub-interface Ethernet AToM tunnel on a Cisco 7606 with a ES+ linecard: Yields the following misleading error… This is enough to annoy you for some time. […]

Port Monitoring/Mirroring on NX-OS: SPAN Profiles

Port mirroring is a very valuable troubleshooting tool. Cisco calls this SPAN, and it’s pretty easy to do. Cisco’s NX-OS platform does it a little differently than traditional IOS, so I wanted to briefly post a walkthrough. First, you have to set up the monitor session and configure source and destination interfaces: switch(config)# monitor session 1 switch(config-monitor)# source int port-channel 2 both switch(config-monitor)# source int port-channel 3 both switch(config-monitor)# destination interface ethernet 1⁄7 switch(config-monitor)# no shut switch(config-monitor)#

KIClet: Cisco UCS vHBA Template Bug

I found a bug in the vHBA Template creation screen on Cisco UCS 2.0. It’s not too bad, but still a little annoying, and can cause you to have some problems depending on how you have your VSANs set up. If you notice, the default VSAN is selected for my vHBA template. I have named my VSANs “fabric-a” and “fabric-b”. If I drop down the VSAN selector, I have the ability to select the VSAN I have associated with fabric A: