Re: network interface monitoring?

On Thu, Jan 24, 2008 at 10:58:33AM -0500, Yousif Hassan wrote:
Thank you to all who responded.

The suggestion was made to use devd or ifstated. Both sound like
excellent tools, but I'm currently being tripped up by a core problem -
both tools rely on the kernel to notify userland of link state changes
(which makes complete sense!). This is all well and good - but the
current issue I'm seeing is that the link state doesn't get updated
without running "ifconfig" again - is this by design? A known "issue?"

An example:
1. Unplug network cable from bfe0
2. I run ifconfig
3. I see that interface bfe0's status is "no carrier". Good.
4. I plug the cable into bfe0
5. Wait... wait... look in /var/log/messages... wait more.. NO STATE
CHANGE - the longest I've waited was 2 minutes, which is already too
long
6. run "ifconfig" again
7. Link state immediately changes, logs to /var/log/messages, devd
scripts run

Is this a known behavior? It seems like the link state changes should
happen automatically, without something to "trigger" them. Isn't there
some kind of poll or interrupt sequence? I'm on 6.3 RC2 (will upgrade
to 6.3-RELEASE imminently) but can't imagine this code changed? Does
this work differently/better in 7.0?

It's known but not well understood and is a driver bug.

-- Brooks

Attachment: pgpcqOsaudIGn.pgp
Description: PGP signature

Relevant Pages

  • Re: network interface monitoring?
    ... The suggestion was made to use devd or ifstated. ... both tools rely on the kernel to notify userland of link state changes ... scripts run ... It seems like the link state changes should ...
    (freebsd-net)
  • Re: network interface monitoring?
    ... The suggestion was made to use devd or ifstated. ... both tools rely on the kernel to notify userland of link state changes ... I run ifconfig ... It seems like the link state changes should ...
    (freebsd-net)
  • Re: network interface monitoring?
    ... both tools rely on the kernel to notify userland of link state changes ... It seems like the link state changes should ... struct bfe_softc *sc; ...
    (freebsd-net)
  • Re: network interface monitoring?
    ... First the good news - your patch appears to solve nearly all of the ... then the link state changes get queued up (as ... For all I know, this might be unrelated to your driver patch, ...
    (freebsd-net)
  • Re: network interface monitoring?
    ... First the good news - your patch appears to solve nearly all of the ... then the link state changes get queued up (as ... For all I know, this might be unrelated to your driver patch, ...
    (freebsd-net)