"You've asked for it" series

Analyzing Google query strings that brought visitors to my blog (StatCounter is an excellent free tool to do this job), I usually find interesting (often repeating) queries that are not yet answered in my blog. Obviously there are not too many good answers on other web sites, otherwise Google users would probably not click on a hit on the second or third page (where my blog usually appears for more generic queries).

So, to help my fellow networking engineers, I've decided to start a series of "You've asked for it" articles answering the questions that brought many of you to my site in the first place (and, don't forget, you can always send me an interesting question with the Send a message link on my bio page.


  1. Hello Ivan. Thanks for all your blogs. I'm currently struggling with TCL and EEM on a cisco6500 and have found much valuable information here. However, there's an issue I cannot seem to solve and I was wondering if you knew some remedy.

    The problem is that I am trying to write an already set eem variable from within a tcl script. Let's call it action_flag1. It is of boolean value and I can well read it in my script. Problem is, I can't change the variable to a different value. Everytime I try to, it seems like the interpreter creates a new variable under the same name that is only visible during runtime. The only workaround I've figured out so far is pretty dowdy: cli_exec the commands

    #conf t
    #event manager variable action_flag1 [value].

    ...that does the trick but maybe you know a more elegant way?
  2. There is a more elegant way (or at least I suspect there is), but I have to test it first. Will write a blog post when I get the results.
  3. Hi Ivan,

    I have generally seen that generally the vendors do not guarantee full bandwith. They say only 85-90% of the bandwidth is usable for data traffic and the rest is not guaranteed as it is used by network overheads? I couldn't find any answer for this network overheads. Can you please tell me what other overheads come into picture from the service provider end.

    Thanking you in anticipation...
Add comment