Tag: config

Doing a lot on Nexus 9000 series datacenter boxes (N9K) lately? Sure you’re missing the good old ‘wr’ command to save your last startup-config into running-config.

NXOS architecture guys decided that you should be really well concentrated when deciding to save your nice new configuration to survive device reboot and type: N9K_1(config)# copy running-config startup-config. Just typing ‘wr’ into the console would be too nice right? Let’s use the alias configuration and bring that command back to the box.

There is always the option to edit a file locally on your computer in notepad++ and then upload it to Cisco device.

With this trick, you can write or edit a file from Flash memory directly from Cisco IOS console. If you need it for whatever reason, maybe to change something in the config file or something else, this is the way to do it.

I was using if for my next article lab where I needed a file on the flash with at least 1600 bytes so I can pull it from neighbouring router with HTTP and check some details in new TCP connection. It was faster to just create the file directly on the router flash and not creating it on my laptop and then transferring it with FTP or TFTP.

I already wrote about Control Plane Protection in one of my previous posts focused on Cisco device configuration. Here we will make the same thing on Juniper device, I was using Juniper SRX300 and Juniper SRX1500 devices in my lab.

CoPP ??

Control Plane Protection (CoPP) is a method of protecting processor unit, running services on your network device, against excessive flooding. Excessive flooding of traffic aimed towards your router/firewall processor, being that valid or malicious, is always undesirable and can also be dangerous.

A network device, which starts the receive more control traffic that his processor can process, will eventually experience control traffic packet drops and it will lead to some of the router functions to become unstable. Some of the most common control traffic generating services on a router are routing protocols with different update packets, Spanning Tree with BPDU packets, HSRP, CDP, ARP, and different management traffic services like SSH, SNMP, RADIUS etc.

Some of those control plane traffic types are more important than others but they all have in common the fact that they don’t normally use much bandwidth to function. Having that in mind, it is easy to conclude that the situation above with router processor at 100% because of control plane traffic is most surely caused by a DDoS attack towards your device.

More unusual is the situation when a neighboring device is experiencing some kind of malfunction which makes him send large amounts of control plane traffic out of his interfaces towards your device.

CoPP is the best way to avoid this kind of attacks or malfunctions to get in the way of your network device stability. CoPP is basically configuration of QoS inbound to your device control plane (CPU).

CoPP Best Practices

The way to configure CoPP in the most stable and effective way is to use guaranteed minimal available bandwidth for each control plane traffic type.

…There’s a nice little pdf to get you through

HP is aware that most of networking engineers start their learning process in Cisco Networking Academy. Is is a normal course of events if you want to learn networking. Cisco has the very best study materials and best, carefully developed syllabus that is both high quality and most detailed in the world of networking. Not to mention the high reputation that engineers get with Cisco certificates standing by their names.

On the other hand, when you take an average mid-size business customer today you will probably see that he is mostly concerned about the price and not so much about the feature-set and robustness of IT equipment. And there you have your situation in which customer decides to go with HP rather than Cisco gear in their communication closet.