Archived; click post to view.
Excerpt: 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)# Notice that I configured both downstream port-channels to be my source interfaces, and that I used the “both” keyword. This means that any traffic going over either port channel, in either…
Port Monitoring/Mirroring on NX-OS: SPAN Profiles
KIClet: Cisco UCS vHBA Template Bug
Archived; click post to view.
Excerpt: 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: However, once I’ve done so, and I change to fabric B, I drop down the selector again, and I now am able…
KIClet: NX-OS Default Switchport State
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Excerpt: Cisco switches (and the vast majority of other vendors) ship their switches with all ports in the enabled state. This allows someone with no networking background to plug stuff in, the switch starts learning MAC addresses, and everything works just fine. Sometimes it’s necessary from a security perspective to change this default behavior, so the network engineer is forced to “no shut” every port he or she wishes to use. In NX-OS this is a particularly interesting subject because it also is a security best practice to do this, not only for your Ethernet ports but also for Fibre Channel. The command…
New Post Type: KIClets
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Excerpt: My time lately has been just blasted. I’m being placed into new projects with a large company that involves just about every technology found in a datacenter, and as a result, my spare time is….nonexistent. My knowledge levels in many areas continues to increase, and my need to spew some of it onto the internet in the form of helpful posts, or opinions is not quenched, but unfortunately I do not have a ton of time to dedicate to full-on blog posts during the week. As a result, I will be posting blog posts in smaller form when I feel the…
