We have many portchannels running between our core switches and access switches. Those portchannel members are getting QoS queueing drops intermittently and it is not happening to specific interfaces. Since it is production environment, we are unable to do any diagnostics.
Current Interface Queueing config... -------------------------------
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In brief, most often drops are caused by a burst of traffic exceeding the egress bandwidth. When that happens, packets queue, but queues only hold so many packets. When queues overflow, you get drops.
Depending on your device capabilities, you might reduce drops by increasing queuing resources (adds to latency, though) or by using a "better" drop strategy. (Basically, some flows, e.g. react to drops. So, by dropping sooner, they slow, and you avoid an all out-of-hand drop situation. You still gets drops, but less.)
To do it "right", you need to understand your traffic, and your device capabilities. Malcolm's reference looks to be a nice starting point.
To be clear, there's often much you can do with QoS settings, but understanding device capabilities extends to fully understanding all your hardware's features. For example, your 6724-SFP is one of the better cards for the 6500 series. It's major limitation is, for raw performance, it's slightly oversubscribed, i.e. 24:20. Some other 6500 line cards, though, do support more buffering per port. (Whether that is really of benefit, depends on the needs of your traffic.)
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.