Last week, after I upgraded an ISR4K to version 17.12.64, we encountered an issue where, after entering the password while SSH to the router, i received the error below. There was not much information specific to Cisco about why this occurred. However, there was generic information on the internet regarding this error, which did not…
Category: Network
Perpetual PoE and Fast PoE
The number of endpoints using PoE has grown significantly. PoE is an IEEE standard that delivers power to devices via an RJ45 cable, eliminating the need for a separate power cable. This reduces the cabling needed for device connections. However, have you considered the issue of rebooting the switch causing all powered devices (PDs) to…
Understanding Cisco Serial Numbers
The serial number of a Cisco device tells you when and where it was made. It has this format: LLLYYWWXXXX. LLL is the location code, YY is the year code, WW is the week code, and XXXX is a unique identifier.YY is the year code, which is the number of years since 1996. Here are…
File System Check and Repair for Cisco IOS
The customer was attempting to add a new VLAN, but it was not appearing on a couple of the switches. The IT team approached us, suggesting that we hold the WIFI migration as they needed to replace the switch due to issues with Flash. They were unable to see the files in the flash when…
Recommended Cabling for DNA Appliance
Recommended Cabling for 44 and 56-Core Appliance Recommended Cabling for 112-Core Appliance
Show tech-support confidential
Have you ever thought of hiding sensitive information’s when sharing a show tech files? Form Cisco IOS XE Amsterdam 17.3.x with show tech-support, Cisco introduced a keyword confidential which hide sensitive information.. show tech-support confidential : The confidential keyword was introduced, to mask sensitive information in the output of show tech-support command When using show…
Things I learned from 1 Gbps Home internet Customer
Few Days back I was working with a customer who subscribed 1Gbps Home Internet connection. He called us to investigate the network devices and make sure that 1 Gbps is available over the LAN. I Visited the customer with my 4 years old Dell laptop which has a Lan port of 1G speed. Even though…
Cisco CLI Analyzer
We all are familiar with the term Quarterly/half Yearly Helath checks. its a part of Annual Maintenance Contract. Without making use of a tool, conducting HC is impossible. Many engineer does the HC just by checking the versions. Cisco provide us a nice tool called CLI analyzer which connects with internal TAC tools and knowledge…
Move to Type 9 password
Its highly recommended to replace your type 5 and 7 passwords with type 9 passwords. Many of us are aware that type 5 and type 7 passwords can be decrypted using online tools but many still not. Todays blog is all about configuring type 9 password. You can try decrypting type 5 and 7 password…
Remove RSA host key using ssh-keygen
nithineluvathingal@EluS-MacBookPRO ~ % ssh administrator@198.18.133.3 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)! It is also possible that a host key has just been changed. The fingerprint for the RSA key…
CRAZY NETWORKING 