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Re: ifconfig delay on up



>>>>> "dm" == der Mouse <mouse%Rodents-Montreal.ORG@localhost> writes:

    dm> 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.''

    dm> (or, when possible, to set it to assume spanning tree
    dm> will show no loops and thus start forwarding immediately, to
    dm> be changed later if appropriate).

right, the vocational school will have taught your high school
graduate netadmin to set cisco's 'portfast' feature for an old
network, or for a new network to set 802.1w RST mode and configure the
port as an edge port.  In both cases, spanning tree remains active and
the delay is gone.  The first case is not ``standard'', and the second
case is.  The second case may be marginally safer.  and the email you
get back from netadmin probably says something like ``k., done''
leading to the confusion.  You tell everyone ``after disabling
spanning tree our Issues went away.''  not so.

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, and if you did it, it would disable certain hacks
for avoiding storms (some documented some not), and if the hacks did
not work and you did encounter a storm it could last until you remove
the loop with spanning tree off, but it'll only last about 1 minute
with portfast / 802.1w-edge.

If you want to get equivalent or maybe slightly less level of storm
safety to the portfast / 802.1w edge without reconfiguring the big
switch at all, plug some crappy hub-like SOHO office switch that
doesn't support spanning tree into your office network jack, and plug
the alpha into that.  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.
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.

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