Re: Deleting child qdisc doesn't reset parent to default qdisc?

From: Eric Dumazet
Date: Thu Apr 14 2016 - 12:41:04 EST


On Thu, 2016-04-14 at 18:22 +0200, Phil Sutter wrote:

> And those being invisible can be overridden using 'tc qd add', right?
> AFAIR they're not listed because they don't properly register, so the
> system doesn't care to override them. In this case we could change all
> classful qdiscs to restore the default qdisc if a leaf qdisc is being
> deleted instead of noop (which is probably not what the user wants
> anyway).

Even if they properly register, they are not visible.

Take a look at
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=95dc19299f741c986227ec33e23cbf9b3321f812

for some context.

When a default pfifo is created on say a HTB class, you do not see it by
default in a dump.

If you have 100 HTB classes, HTB created 100 pfifo just fine, and it
works, unless an admin tries to delete them maybe ;)