[LARTC] how to debug RTNETLINK invalid argument?

[Larry Brigman]

On 5/23/06, George Nychis <gnychis at cmu.edu> wrote:
> Larry Brigman wrote:
> > On 5/23/06, George Nychis <gnychis at cmu.edu> wrote:
> >> Larry Brigman wrote:
> >> > On 5/23/06, George Nychis <gnychis at cmu.edu> wrote:
> >> >> Hey,
> >> >>
> >> >> I am getting an invalid argument trying to insert a qdisc:
> >> >>
> >> >> [root at emu-5 iproute2]# tc qdisc add dev eth0 root xcp capacity 50Mbit
> >> >> limit 500
> >> >> RTNETLINK answers: Invalid argument
> >> >>
> >> >> I'm not sure whats wrong here, because i can successfully insert this
> >> >> qdisc on other computers of mine.
> >> >>
> >> >> How can i debug this?
> >> >>
> >> > Check to see which kernel versions you have on the boxes that work and
> >> > the one that
> >> > does not.  Also check to see if you have the latest version of
> >> > iproute2 installed on the
> >> > machine that does not work.
> >> >
> >>
> >> They are both running the exact same kernel and version of iproute2,
> >> however they are in different environments, what could the environment
> >> have to do with it?
> >>
> > Modules that are not loaded?  modprobe.conf?
> > lsmod on both boxes looking for specific networking modules.
> >
>
> What modules would qdisc's be dependent on?  The weird thing is, netem
> works on both machines... therefore I know qdisc's in general are
> working.  Lets just say its not working on my other machine, how do i go
> about debugging it on the one machine alone?
>

Has the tc command been changed recently from your customized version back
to the standard release (ie yum running via cron) or your environment
path changed to
pick up the wrong tc command?