Port-alpha archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: ifconfig delay on up

>> is to disable spanning tree on that port
> That is what the software people always ask the netadmins to do.
> ``spanning tree is causing me problems.  I don't know what it is but
> i have Issues.  please disable it.''

Now, now.  While I would hardly claim that doesn't happen, it's rather
unfair to tar all disabling of ST with the same brush.  Sometimes,
disabling it _is_ the right answer - and when a software type asks a
netadmin to turn it off, "I don't know what it is" sometimes is wrong
(though that's orthogonal to whether the request is appropriate).

> But if you have to stand in for the net admin without going to the
> vocational school first, you should not be disabling spanning tree.
> It's not necessary,

Sometimes, maybe, it is.  And sometimes it's a right answer even if
it's not, strictly, necessary.  (A home network with only one switch is
a good example: the only thing spanning tree brings to such a network
is insulation against possible future expansion that might introduce
loops.  While this is arguably a good thing, spanning tree also has
prices, such as the delay that started this thread off, and a little
noise traffic.)

> at least until the netadmin's little alarm goes off, and he comes
> around to, if he's any good, take away your switch before you drape a
> cable into the next cube and break the network.

Now now.  Take your "all setups are the same" blinkers off; not all
networks have separate netadmins.  And not all netadmins would do that
- not even all good netadmins; part of being a good netadmin is knowing
when something like that _is_ a right answer.  And, mercifully, not all
environments - not even all work environments - are cube farms.

> anyway it should work long enough to figure out if this is really
> your problem.


> I admit the whole thing is kind of silly.  but yeah, don't go around
> turning off spanning tree.

Er.  Rather, don't go around turning off spanning tree carelessly -
especially on networks others administer without consulting with them

On a home network where it'll be a cold day in hell before there's ever
a second switch involved, on a network that's yours (where any prices
to be paid fromk disabling ST will be on your head)...

Of course, if you know exactly what ST is and when you should and
shouldn't turn it off, you don't need any of this advice. :)  (That's
unlikely to be the OP, or the question wouldn't've arisen, but this is
likely to be read by others.)

/~\ The ASCII                             Mouse
\ / Ribbon Campaign
 X  Against HTML                mouse%rodents-montreal.org@localhost
/ \ Email!           7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B

Home | Main Index | Thread Index | Old Index