Re: tc filter show dev xxx doesn't output anything

Re: tc filter show dev xxx doesn't output anything

[Lee Brown]

Hi,

I've only played around with filters before, but I seem to remember
that 'tc filter show dev eth0' used to display all the filters.  Now
there is no output at all.  I moved from Centos5 (2.6.18) to 6
(2.6.32) so I've no clue where this was introduced.  Same happens on
slackware 14.1 (3.10.17) there's no output.

Is the new behaviour intentional?

Thanks -- lee

Re: tc filter show dev xxx doesn't output anything

[Benjamin Kiessling]

Hi,

On 05/23, Lee Brown wrote:
> Hi,
> 
> I've only played around with filters before, but I seem to remember
> that 'tc filter show dev eth0' used to display all the filters.  Now
> there is no output at all.  I moved from Centos5 (2.6.18) to 6
> (2.6.32) so I've no clue where this was introduced.  Same happens on
> slackware 14.1 (3.10.17) there's no output.
> 
> Is the new behaviour intentional?

It's probably a bug but it hasn't been working for a really long time
now. In fact I can't remember it ever outputting anything at all (at
least since Debian etch). The TC framework is a piling mass of spagetti
code with almost no maintenance done. People keep adding qdiscs but as
far as I know nobody runs comprehensive test cases to ensure stuff does
not break.

All best,
Ben

Re: tc filter show dev xxx doesn't output anything

[Andy Furniss]

Lee Brown wrote:
> Hi,
>
> I've only played around with filters before, but I seem to remember
> that 'tc filter show dev eth0' used to display all the filters.  Now
> there is no output at all.  I moved from Centos5 (2.6.18) to 6
> (2.6.32) so I've no clue where this was introduced.  Same happens on
> slackware 14.1 (3.10.17) there's no output.
>
> Is the new behaviour intentional?

I doubt it - of course you don't say what the filters are or what qdisc 
they are attached to.

On a box which is not used for tc stuff - current kernel + probably year 
old tc.

tc qdisc add dev eth0 root handle 1:0 prio
tc filter add dev eth0 parent 1:0 u32 match u32 0 0 flowid 1:1
tc filter show dev eth0
filter parent 1: protocol all pref 49152 u32
filter parent 1: protocol all pref 49152 u32 fh 800: ht divisor 1
filter parent 1: protocol all pref 49152 u32 fh 800::800 order 2048 key 
ht 800 bkt 0 flowid 1:1
   match 00000000/00000000 at 0